diff --git a/Doc/library/struct.rst b/Doc/library/struct.rst
index fa0fb19d852f86..f504f931f0fa20 100644
--- a/Doc/library/struct.rst
+++ b/Doc/library/struct.rst
@@ -227,32 +227,32 @@ platform-dependent.
 +--------+--------------------------+--------------------+----------------+------------+
 | ``c``  | :c:expr:`char`           | bytes of length 1  | 1              |            |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``b``  | :c:expr:`signed char`    | integer            | 1              | \(1), \(2) |
+| ``b``  | :c:expr:`signed char`    | int                | 1              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``B``  | :c:expr:`unsigned char`  | integer            | 1              | \(2)       |
+| ``B``  | :c:expr:`unsigned char`  | int                | 1              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
 | ``?``  | :c:expr:`_Bool`          | bool               | 1              | \(1)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``h``  | :c:expr:`short`          | integer            | 2              | \(2)       |
+| ``h``  | :c:expr:`short`          | int                | 2              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``H``  | :c:expr:`unsigned short` | integer            | 2              | \(2)       |
+| ``H``  | :c:expr:`unsigned short` | int                | 2              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``i``  | :c:expr:`int`            | integer            | 4              | \(2)       |
+| ``i``  | :c:expr:`int`            | int                | 4              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``I``  | :c:expr:`unsigned int`   | integer            | 4              | \(2)       |
+| ``I``  | :c:expr:`unsigned int`   | int                | 4              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``l``  | :c:expr:`long`           | integer            | 4              | \(2)       |
+| ``l``  | :c:expr:`long`           | int                | 4              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``L``  | :c:expr:`unsigned long`  | integer            | 4              | \(2)       |
+| ``L``  | :c:expr:`unsigned long`  | int                | 4              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``q``  | :c:expr:`long long`      | integer            | 8              | \(2)       |
+| ``q``  | :c:expr:`long long`      | int                | 8              | \(2)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``Q``  | :c:expr:`unsigned long   | integer            | 8              | \(2)       |
+| ``Q``  | :c:expr:`unsigned long   | int                | 8              | \(2)       |
 |        | long`                    |                    |                |            |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``n``  | :c:type:`ssize_t`        | integer            |                | \(3)       |
+| ``n``  | :c:type:`ssize_t`        | int                |                | \(2), \(3) |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``N``  | :c:type:`size_t`         | integer            |                | \(3)       |
+| ``N``  | :c:type:`size_t`         | int                |                | \(2), \(3) |
 +--------+--------------------------+--------------------+----------------+------------+
 | ``e``  | :c:expr:`_Float16`       | float              | 2              | \(4), \(6) |
 +--------+--------------------------+--------------------+----------------+------------+
@@ -268,7 +268,7 @@ platform-dependent.
 +--------+--------------------------+--------------------+----------------+------------+
 | ``p``  | :c:expr:`char[]`         | bytes              |                | \(8)       |
 +--------+--------------------------+--------------------+----------------+------------+
-| ``P``  | :c:expr:`void \*`        | integer            |                | \(5)       |
+| ``P``  | :c:expr:`void \*`        | int                |                | \(2), \(5) |
 +--------+--------------------------+--------------------+----------------+------------+
 
 .. versionchanged:: 3.3
@@ -342,27 +342,31 @@ Notes:
    The ``'p'`` format character encodes a "Pascal string", meaning a short
    variable-length string stored in a *fixed number of bytes*, given by the count.
    The first byte stored is the length of the string, or 255, whichever is
-   smaller.  The bytes of the string follow.  If the string passed in to
+   smaller.  The bytes of the string follow.  If the byte string passed in to
    :func:`pack` is too long (longer than the count minus 1), only the leading
-   ``count-1`` bytes of the string are stored.  If the string is shorter than
+   ``count-1`` bytes of the string are stored.  If the byte string is shorter than
    ``count-1``, it is padded with null bytes so that exactly count bytes in all
    are used.  Note that for :func:`unpack`, the ``'p'`` format character consumes
-   ``count`` bytes, but that the string returned can never contain more than 255
+   ``count`` bytes, but that the :class:`!bytes` object returned can never contain more than 255
    bytes.
+   When packing, arguments of types :class:`bytes` and :class:`bytearray`
+   are accepted.
 
 (9)
    For the ``'s'`` format character, the count is interpreted as the length of the
-   bytes, not a repeat count like for the other format characters; for example,
+   byte string, not a repeat count like for the other format characters; for example,
    ``'10s'`` means a single 10-byte string mapping to or from a single
    Python byte string, while ``'10c'`` means 10
    separate one byte character elements (e.g., ``cccccccccc``) mapping
    to or from ten different Python byte objects. (See :ref:`struct-examples`
    for a concrete demonstration of the difference.)
-   If a count is not given, it defaults to 1.  For packing, the string is
+   If a count is not given, it defaults to 1.  For packing, the byte string is
    truncated or padded with null bytes as appropriate to make it fit. For
-   unpacking, the resulting bytes object always has exactly the specified number
-   of bytes.  As a special case, ``'0s'`` means a single, empty string (while
+   unpacking, the resulting :class:`!bytes` object always has exactly the specified number
+   of bytes.  As a special case, ``'0s'`` means a single, empty byte string (while
    ``'0c'`` means 0 characters).
+   When packing, arguments of types :class:`bytes` and :class:`bytearray`
+   are accepted.
 
 (10)
    For the ``'F'`` and ``'D'`` format characters, the packed representation uses
diff --git a/Lib/shutil.py b/Lib/shutil.py
index 44ccdbb503d4fb..45cbe4c855b462 100644
--- a/Lib/shutil.py
+++ b/Lib/shutil.py
@@ -1317,27 +1317,9 @@ def _unpack_zipfile(filename, extract_dir):
     if not zipfile.is_zipfile(filename):
         raise ReadError("%s is not a zip file" % filename)
 
-    zip = zipfile.ZipFile(filename)
-    try:
-        for info in zip.infolist():
-            name = info.filename
-
-            # don't extract absolute paths or ones with .. in them
-            if name.startswith('/') or '..' in name:
-                continue
-
-            targetpath = os.path.join(extract_dir, *name.split('/'))
-            if not targetpath:
-                continue
-
-            _ensure_directory(targetpath)
-            if not name.endswith('/'):
-                # file
-                with zip.open(name, 'r') as source, \
-                        open(targetpath, 'wb') as target:
-                    copyfileobj(source, target)
-    finally:
-        zip.close()
+    with zipfile.ZipFile(filename) as zip:
+        zip._ignore_invalid_names = True
+        zip.extractall(extract_dir)
 
 def _unpack_tarfile(filename, extract_dir, *, filter=None):
     """Unpack tar/tar.gz/tar.bz2/tar.xz/tar.zst `filename` to `extract_dir`
diff --git a/Lib/test/test_shutil.py b/Lib/test/test_shutil.py
index a4bd113bc7f1fc..13a3487382dfcf 100644
--- a/Lib/test/test_shutil.py
+++ b/Lib/test/test_shutil.py
@@ -2136,8 +2136,6 @@ def test_make_zipfile_rootdir_nodir(self):
     def check_unpack_archive(self, format, **kwargs):
         self.check_unpack_archive_with_converter(
             format, lambda path: path, **kwargs)
-        self.check_unpack_archive_with_converter(
-            format, FakePath, **kwargs)
         self.check_unpack_archive_with_converter(format, FakePath, **kwargs)
 
     def check_unpack_archive_with_converter(self, format, converter, **kwargs):
@@ -2194,6 +2192,71 @@ def test_unpack_archive_zip(self):
         with self.assertRaises(TypeError):
             self.check_unpack_archive('zip', filter='data')
 
+    def test_unpack_archive_zip_badpaths(self):
+        srcdir = self.mkdtemp()
+        zipname = os.path.join(srcdir, 'test.zip')
+        abspath = os.path.join(srcdir, 'abspath')
+        with zipfile.ZipFile(zipname, 'w') as zf:
+            zf.writestr(abspath, 'badfile')
+            zf.writestr(os.sep + abspath, 'badfile')
+            zf.writestr('/abspath', 'badfile')
+            zf.writestr('C:/abspath', 'badfile')
+            zf.writestr('D:\\abspath', 'badfile')
+            zf.writestr('E:abspath', 'badfile')
+            zf.writestr('F:/G:/abspath', 'badfile')
+            zf.writestr('//server/share/abspath', 'badfile')
+            zf.writestr('\\\\server2\\share\\abspath', 'badfile')
+            zf.writestr('../relpath', 'badfile')
+            zf.writestr(os.pardir + os.sep + 'relpath2', 'badfile')
+            zf.writestr('good/file', 'goodfile')
+            zf.writestr('good..file', 'goodfile')
+
+        dstdir = os.path.join(self.mkdtemp(), 'dst')
+        unpack_archive(zipname, dstdir)
+        self.assertTrue(os.path.isfile(os.path.join(dstdir, 'good', 'file')))
+        self.assertTrue(os.path.isfile(os.path.join(dstdir, 'good..file')))
+        self.assertFalse(os.path.exists(abspath))
+        self.assertFalse(os.path.exists(os.path.join(dstdir, 'abspath')))
+        self.assertFalse(os.path.exists(os.path.join(dstdir, 'G_')))
+        self.assertFalse(os.path.exists(os.path.join(dstdir, 'server')))
+        if os.name != 'nt':
+            self.assertTrue(os.path.isfile(os.path.join(dstdir, 'C:', 'abspath')))
+            self.assertTrue(os.path.isfile(os.path.join(dstdir, 'D:\\abspath')))
+            self.assertTrue(os.path.isfile(os.path.join(dstdir, 'E:abspath')))
+            self.assertTrue(os.path.isfile(os.path.join(dstdir, 'F:', 'G:', 'abspath')))
+            self.assertTrue(os.path.isfile(os.path.join(dstdir, '\\\\server2\\share\\abspath')))
+        if os.pardir == '..':
+            self.assertFalse(os.path.exists(os.path.join(dstdir, '..', 'relpath')))
+            self.assertFalse(os.path.exists(os.path.join(dstdir, 'relpath')))
+        else:
+            self.assertTrue(os.path.isfile(os.path.join(dstdir, '..', 'relpath')))
+        self.assertFalse(os.path.exists(os.path.join(dstdir, os.pardir, 'relpath2')))
+        self.assertFalse(os.path.exists(os.path.join(dstdir, 'relpath2')))
+
+        dstdir2 = os.path.join(self.mkdtemp(), 'dst')
+        os.mkdir(dstdir2)
+        with os_helper.change_cwd(dstdir2):
+            unpack_archive(zipname, '')
+            self.assertTrue(os.path.isfile(os.path.join('good', 'file')))
+            self.assertTrue(os.path.isfile('good..file'))
+            self.assertFalse(os.path.exists(abspath))
+            self.assertFalse(os.path.exists('abspath'))
+            self.assertFalse(os.path.exists('C_'))
+            self.assertFalse(os.path.exists('server'))
+            if os.name != 'nt':
+                self.assertTrue(os.path.isfile(os.path.join('C:', 'abspath')))
+                self.assertTrue(os.path.isfile('D:\\abspath'))
+                self.assertTrue(os.path.isfile('E:abspath'))
+                self.assertTrue(os.path.isfile(os.path.join('F:', 'G:', 'abspath')))
+                self.assertTrue(os.path.isfile('\\\\server2\\share\\abspath'))
+            if os.pardir == '..':
+                self.assertFalse(os.path.exists(os.path.join('..', 'relpath')))
+                self.assertFalse(os.path.exists('relpath'))
+            else:
+                self.assertTrue(os.path.isfile(os.path.join('..', 'relpath')))
+            self.assertFalse(os.path.exists(os.path.join(os.pardir, 'relpath2')))
+            self.assertFalse(os.path.exists('relpath2'))
+
     def test_unpack_registry(self):
 
         formats = get_unpack_formats()
diff --git a/Lib/zipfile/__init__.py b/Lib/zipfile/__init__.py
index 51e0ce9fa36d7e..1e0cc5f6234f28 100644
--- a/Lib/zipfile/__init__.py
+++ b/Lib/zipfile/__init__.py
@@ -1410,6 +1410,7 @@ class ZipFile:
 
     fp = None                   # Set here since __del__ checks it
     _windows_illegal_name_trans_table = None
+    _ignore_invalid_names = False
 
     def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=True,
                  compresslevel=None, *, strict_timestamps=True, metadata_encoding=None):
@@ -1890,21 +1891,31 @@ def _extract_member(self, member, targetpath, pwd):
 
         # build the destination pathname, replacing
         # forward slashes to platform specific separators.
-        arcname = member.filename.replace('/', os.path.sep)
-
-        if os.path.altsep:
+        arcname = member.filename
+        if os.path.sep != '/':
+            arcname = arcname.replace('/', os.path.sep)
+        if os.path.altsep and os.path.altsep != '/':
             arcname = arcname.replace(os.path.altsep, os.path.sep)
         # interpret absolute pathname as relative, remove drive letter or
         # UNC path, redundant separators, "." and ".." components.
-        arcname = os.path.splitdrive(arcname)[1]
+        drive, root, arcname = os.path.splitroot(arcname)
+        if self._ignore_invalid_names and (drive or root):
+            return None
+        if self._ignore_invalid_names and os.path.pardir in arcname.split(os.path.sep):
+            return None
         invalid_path_parts = ('', os.path.curdir, os.path.pardir)
         arcname = os.path.sep.join(x for x in arcname.split(os.path.sep)
                                    if x not in invalid_path_parts)
         if os.path.sep == '\\':
             # filter illegal characters on Windows
-            arcname = self._sanitize_windows_name(arcname, os.path.sep)
+            arcname2 = self._sanitize_windows_name(arcname, os.path.sep)
+            if self._ignore_invalid_names and arcname2 != arcname:
+                return None
+            arcname = arcname2
 
         if not arcname and not member.is_dir():
+            if self._ignore_invalid_names:
+                return None
             raise ValueError("Empty filename.")
 
         targetpath = os.path.join(targetpath, arcname)
diff --git a/Misc/NEWS.d/next/Security/2026-03-29-12-51-33.gh-issue-146581.4vZfB0.rst b/Misc/NEWS.d/next/Security/2026-03-29-12-51-33.gh-issue-146581.4vZfB0.rst
new file mode 100644
index 00000000000000..98e65549d79016
--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2026-03-29-12-51-33.gh-issue-146581.4vZfB0.rst
@@ -0,0 +1,5 @@
+Fix vulnerability in :func:`shutil.unpack_archive` for ZIP files on Windows
+which allowed to write files outside of the destination tree if the patch in
+the archive contains a Windows drive prefix. Now such invalid paths will be
+skipped. Files containing ".." in the name (like "foo..bar") are no longer
+skipped.
diff --git a/Misc/NEWS.d/next/Security/2026-04-24-23-15-42.gh-issue-148252.8BLmzd.rst b/Misc/NEWS.d/next/Security/2026-04-24-23-15-42.gh-issue-148252.8BLmzd.rst
new file mode 100644
index 00000000000000..531ea2348ffdef
--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2026-04-24-23-15-42.gh-issue-148252.8BLmzd.rst
@@ -0,0 +1,3 @@
+Fixed string table and sample record bounds checks in :mod:`!_remote_debugging`
+when decoding certain ``.pyb`` inputs on 32-bit builds. Patch by Maurycy
+Pawłowski-Wieroński.
diff --git a/Misc/NEWS.d/next/Security/2026-04-26-17-49-58.gh-issue-149017.EiVFPo.rst b/Misc/NEWS.d/next/Security/2026-04-26-17-49-58.gh-issue-149017.EiVFPo.rst
new file mode 100644
index 00000000000000..6aa7efb68a1981
--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2026-04-26-17-49-58.gh-issue-149017.EiVFPo.rst
@@ -0,0 +1 @@
+Update bundled `libexpat <https://libexpat.github.io/>`_ to version 2.8.0.
diff --git a/Misc/sbom.spdx.json b/Misc/sbom.spdx.json
index ed9c08016808bb..aaeffd58e799ed 100644
--- a/Misc/sbom.spdx.json
+++ b/Misc/sbom.spdx.json
@@ -48,11 +48,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "9dfd09a3be37618cbcea380c2374b2b8f0288f57"
+          "checksumValue": "5343adc95840915b022b1d4524d0acb66b369ba2"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "26805a0d1a7a6a5cd8ead9cf7f4da29f63f0547a9ad41e80dba4ed9fe1943140"
+          "checksumValue": "1ec3bad08b6864c2c479e1fd941038c2dcd24c6d9a16400f4da54912d95aa321"
         }
       ],
       "fileName": "Modules/expat/expat.h"
@@ -62,11 +62,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "da0328279276800cc747ea7da23886a3f402ccb3"
+          "checksumValue": "d8f9211d52ff0384e229e4d4d56adae5db2d7f91"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "15a80e414e9e7c43edba64b1608a77c724387070138693f9e9bcca49c78a2df7"
+          "checksumValue": "b77f8192baf90aaa41f7023bc68fd1f22ab2552f98758271a1e090544537def5"
         }
       ],
       "fileName": "Modules/expat/expat_external.h"
@@ -90,11 +90,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "6a4a232233ba1034c3f2b459159d502e9b2d413b"
+          "checksumValue": "2555e70b29c1efc0af40879daafd12f8b36aca2c"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "c803935722f0dbdeeede7f040028fb119135e96dfad949479f8a5304b885bdd6"
+          "checksumValue": "4feb1df53898a48ae0ae04b5d0352c90395c8e693e5c2675f8ced41903d6fa94"
         }
       ],
       "fileName": "Modules/expat/internal.h"
@@ -174,11 +174,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "0c74fbd48dd515c58eeb65b7e71b29da94be4694"
+          "checksumValue": "cb0af01558ec7b6474d2bd0c9386380c82618e8f"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "861e7a50ce81f9f16b42d32a9caa4f817d962b274b2929b579511c6f76d348d4"
+          "checksumValue": "6745a6b8cdd7344d4bd8f27f605363ed746e57ff02d4ebce3eb1806579cd030f"
         }
       ],
       "fileName": "Modules/expat/xmlparse.c"
@@ -188,11 +188,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "7cff4d7210f046144f5fa635113f9c26f30fe3d3"
+          "checksumValue": "c8769fcb93f00272a6e6ca560be633649c817ff7"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "eaa6c327f9db4a5cec768d0c01927fea212d3ef4d4f970ebc0a98b9f3602784c"
+          "checksumValue": "5b81f0eb0e144b611dbd1bc9e6037075a16bff94f823d57a81eb2a3e4999e91a"
         }
       ],
       "fileName": "Modules/expat/xmlrole.c"
@@ -216,11 +216,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "48b7aa6503302d4157c61a8763629f3236c23502"
+          "checksumValue": "63e4766a09e63760c6518670509198f8d638f4ad"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "75da65603e99837fd3116f1453372efd556f9f97d8de73364594dd78b3c8ec54"
+          "checksumValue": "0ad3f915f2748dc91bf4e4b4a50cf40bf2c95769d0eca7e3b293a230d82bb779"
         }
       ],
       "fileName": "Modules/expat/xmltok.c"
@@ -272,11 +272,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "705842f8a09b09cc021d82a71ab03344bfd07b0a"
+          "checksumValue": "41b8c8fc275882c76d4210b7d40a18e506b07147"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "f95a2b4b7efda40f5faf366537cb20a57dddbad9655859d2e304f5e75f6907cc"
+          "checksumValue": "b2188c7e5fa5b33e355cf6cf342dfb8f6e23859f2a6b1ddf79841d7f84f7b196"
         }
       ],
       "fileName": "Modules/expat/xmltok_ns.c"
@@ -1730,14 +1730,14 @@
       "checksums": [
         {
           "algorithm": "SHA256",
-          "checksumValue": "9931f9860d18e6cf72d183eb8f309bfb96196c00e1d40caa978e95bc9aa978b6"
+          "checksumValue": "c7cec5f60ea3a42e7780781c6745255c19aa3dbfeeae58646b7132f88dc24780"
         }
       ],
-      "downloadLocation": "https://github.com/libexpat/libexpat/releases/download/R_2_7_5/expat-2.7.5.tar.gz",
+      "downloadLocation": "https://github.com/libexpat/libexpat/releases/download/R_2_8_0/expat-2.8.0.tar.gz",
       "externalRefs": [
         {
           "referenceCategory": "SECURITY",
-          "referenceLocator": "cpe:2.3:a:libexpat_project:libexpat:2.7.5:*:*:*:*:*:*:*",
+          "referenceLocator": "cpe:2.3:a:libexpat_project:libexpat:2.8.0:*:*:*:*:*:*:*",
           "referenceType": "cpe23Type"
         }
       ],
@@ -1745,7 +1745,7 @@
       "name": "expat",
       "originator": "Organization: Expat development team",
       "primaryPackagePurpose": "SOURCE",
-      "versionInfo": "2.7.5"
+      "versionInfo": "2.8.0"
     },
     {
       "SPDXID": "SPDXRef-PACKAGE-hacl-star",
diff --git a/Modules/_remote_debugging/binary_io.h b/Modules/_remote_debugging/binary_io.h
index d90546078bf68c..18f989f672e103 100644
--- a/Modules/_remote_debugging/binary_io.h
+++ b/Modules/_remote_debugging/binary_io.h
@@ -61,6 +61,7 @@ extern "C" {
 #define HDR_SIZE_COMPRESSION 4
 #define FILE_HEADER_SIZE     (HDR_OFF_COMPRESSION + HDR_SIZE_COMPRESSION)
 #define FILE_HEADER_PLACEHOLDER_SIZE 64
+#define SAMPLE_HEADER_FIXED_SIZE (sizeof(uint64_t) + sizeof(uint32_t) + 1)
 
 static_assert(FILE_HEADER_SIZE <= FILE_HEADER_PLACEHOLDER_SIZE,
               "FILE_HEADER_SIZE exceeds FILE_HEADER_PLACEHOLDER_SIZE");
diff --git a/Modules/_remote_debugging/binary_io_reader.c b/Modules/_remote_debugging/binary_io_reader.c
index aca93e9cb1a30e..6c32ef70ac3f65 100644
--- a/Modules/_remote_debugging/binary_io_reader.c
+++ b/Modules/_remote_debugging/binary_io_reader.c
@@ -258,7 +258,7 @@ reader_parse_string_table(BinaryReader *reader, const uint8_t *data, size_t file
             PyErr_SetString(PyExc_ValueError, "Malformed varint in string table");
             return -1;
         }
-        if (offset + str_len > file_size) {
+        if (offset > file_size || str_len > file_size - offset) {
             PyErr_SetString(PyExc_ValueError, "String table overflow");
             return -1;
         }
@@ -976,8 +976,8 @@ binary_reader_replay(BinaryReader *reader, PyObject *collector, PyObject *progre
     }
 
     while (offset < reader->sample_data_size) {
-        /* Read thread_id (8 bytes) + interpreter_id (4 bytes) */
-        if (offset + 13 > reader->sample_data_size) {
+        /* Read thread_id (8 bytes) + interpreter_id (4 bytes) + encoding byte */
+        if (reader->sample_data_size - offset < SAMPLE_HEADER_FIXED_SIZE) {
             break;  /* End of data */
         }
 
diff --git a/Modules/_remote_debugging/binary_io_writer.c b/Modules/_remote_debugging/binary_io_writer.c
index c129c93efe23c5..0ac6c88d0373a7 100644
--- a/Modules/_remote_debugging/binary_io_writer.c
+++ b/Modules/_remote_debugging/binary_io_writer.c
@@ -23,7 +23,6 @@
  * ============================================================================ */
 
 /* Sample header sizes */
-#define SAMPLE_HEADER_FIXED_SIZE 13      /* thread_id(8) + interpreter_id(4) + encoding(1) */
 #define SAMPLE_HEADER_MAX_SIZE 26        /* fixed + max_varint(10) + status(1) + margin */
 #define MAX_VARINT_SIZE 10               /* Maximum bytes for a varint64 */
 #define MAX_VARINT_SIZE_U32 5            /* Maximum bytes for a varint32 */
@@ -653,10 +652,13 @@ write_sample_with_encoding(BinaryWriter *writer, ThreadEntry *entry,
     memcpy(header_buf, &entry->thread_id, 8);
     memcpy(header_buf + 8, &entry->interpreter_id, 4);
     header_buf[12] = (uint8_t)encoding_type;
-    size_t varint_len = encode_varint_u64(header_buf + 13, timestamp_delta);
-    header_buf[13 + varint_len] = status;
+    size_t varint_len = encode_varint_u64(
+        header_buf + SAMPLE_HEADER_FIXED_SIZE,
+        timestamp_delta);
+    header_buf[SAMPLE_HEADER_FIXED_SIZE + varint_len] = status;
 
-    if (writer_write_bytes(writer, header_buf, 14 + varint_len) < 0) {
+    if (writer_write_bytes(writer, header_buf,
+                           SAMPLE_HEADER_FIXED_SIZE + varint_len + 1) < 0) {
         return -1;
     }
 
diff --git a/Modules/_struct.c b/Modules/_struct.c
index c235e27a415543..47119cb3961e3c 100644
--- a/Modules/_struct.c
+++ b/Modules/_struct.c
@@ -1,7 +1,7 @@
 /* struct module -- pack values into and (out of) bytes objects */
 
 /* New version supporting byte order, alignment and size options,
-   character strings, and unsigned numbers */
+   byte strings, and unsigned numbers */
 
 #ifndef Py_BUILD_CORE_BUILTIN
 #  define Py_BUILD_CORE_MODULE 1
@@ -2297,7 +2297,7 @@ Struct_iter_unpack_impl(PyStructObject *self, PyObject *buffer)
  *
  * Takes a struct object, a tuple of arguments, and offset in that tuple of
  * argument for where to start processing the arguments for packing, and a
- * character buffer for writing the packed string.  The caller must insure
+ * character buffer for writing the packed data.  The caller must ensure
  * that the buffer may contain the required length for packing the arguments.
  * 0 is returned on success, 1 is returned if there is an error.
  *
@@ -2774,8 +2774,8 @@ static struct PyMethodDef module_functions[] = {
 
 PyDoc_STRVAR(module_doc,
 "Functions to convert between Python values and C structs.\n\
-Python bytes objects are used to hold the data representing the C struct\n\
-and also as format strings (explained below) to describe the layout of data\n\
+Python bytes objects are used to hold the data representing the C struct.\n\
+The format string (explained below) describes the layout of data\n\
 in the C struct.\n\
 \n\
 The optional first format char indicates byte order, size and alignment:\n\
@@ -2785,19 +2785,18 @@ The optional first format char indicates byte order, size and alignment:\n\
   >: big-endian, std. size & alignment\n\
   !: same as >\n\
 \n\
-The remaining chars indicate types of args and must match exactly;\n\
+The remaining characters indicate types of args and must match exactly;\n\
 these can be preceded by a decimal repeat count:\n\
-  x: pad byte (no data); c:char; b:signed byte; B:unsigned byte;\n\
-  ?:_Bool; h:short; H:unsigned short; i:int; I:unsigned int;\n\
-  l:long; L:unsigned long; f:float; d:double; e:half-float.\n\
-  F:float complex; D:double complex.\n\
+  x: pad byte (no data); c: char; b: signed byte; B: unsigned byte;\n\
+  ?: _Bool; h: short; H: unsigned short; i: int; I: unsigned int;\n\
+  l: long; L: unsigned long; q: long long; Q: unsigned long long;\n\
+  f: float; d: double; e: half-float;\n\
+  F: float complex; D: double complex.\n\
 Special cases (preceding decimal count indicates length):\n\
-  s:string (array of char); p: pascal string (with count byte).\n\
+  s: byte string (array of char); p: Pascal string (with count byte).\n\
 Special cases (only available in native format):\n\
-  n:ssize_t; N:size_t;\n\
-  P:an integer type that is wide enough to hold a pointer.\n\
-Special case (not in native mode unless 'long long' in platform C):\n\
-  q:long long; Q:unsigned long long\n\
+  n: ssize_t; N: size_t;\n\
+  P: an integer type that is wide enough to hold a pointer.\n\
 Whitespace between formats is ignored.\n\
 \n\
 The variable struct.error is an exception raised on errors.\n");
diff --git a/Modules/expat/expat.h b/Modules/expat/expat.h
index 18dbaebde293bc..79c609f19aa4cf 100644
--- a/Modules/expat/expat.h
+++ b/Modules/expat/expat.h
@@ -45,6 +45,7 @@
 #ifndef Expat_INCLUDED
 #  define Expat_INCLUDED 1
 
+#  include <stdint.h> // for uint8_t
 #  include <stdlib.h>
 #  include "expat_external.h"
 
@@ -917,10 +918,21 @@ XML_SetParamEntityParsing(XML_Parser parser,
    function behavior. This must be called before parsing is started.
    Returns 1 if successful, 0 when called after parsing has started.
    Note: If parser == NULL, the function will do nothing and return 0.
+   DEPRECATED since Expat 2.8.0.
 */
 XMLPARSEAPI(int)
 XML_SetHashSalt(XML_Parser parser, unsigned long hash_salt);
 
+/* Sets the hash salt to use for internal hash calculations.
+   Helps in preventing DoS attacks based on predicting hash function behavior.
+   This must be called before parsing is started.
+   Returns XML_TRUE if successful, XML_FALSE when called after parsing has
+   started or when parser is NULL.
+   Added in Expat 2.8.0.
+*/
+XMLPARSEAPI(XML_Bool)
+XML_SetHashSalt16Bytes(XML_Parser parser, const uint8_t entropy[16]);
+
 /* If XML_Parse or XML_ParseBuffer have returned XML_STATUS_ERROR, then
    XML_GetErrorCode returns information about the error.
 */
@@ -1081,8 +1093,8 @@ XML_SetReparseDeferralEnabled(XML_Parser parser, XML_Bool enabled);
    See https://semver.org
 */
 #  define XML_MAJOR_VERSION 2
-#  define XML_MINOR_VERSION 7
-#  define XML_MICRO_VERSION 5
+#  define XML_MINOR_VERSION 8
+#  define XML_MICRO_VERSION 0
 
 #  ifdef __cplusplus
 }
diff --git a/Modules/expat/expat_config.h b/Modules/expat/expat_config.h
index 09d3161dbc0fb2..70df73c8e00a5f 100644
--- a/Modules/expat/expat_config.h
+++ b/Modules/expat/expat_config.h
@@ -22,5 +22,10 @@
 // bpo-30947: Python uses best available entropy sources to
 // call XML_SetHashSalt(), expat entropy sources are not needed
 #define XML_POOR_ENTROPY 1
+#undef HAVE_ARC4RANDOM
+#undef HAVE_ARC4RANDOM_BUF
+#undef HAVE_GETENTROPY
+#undef HAVE_GETRANDOM
+#undef HAVE_SYSCALL_GETRANDOM
 
 #endif /* EXPAT_CONFIG_H */
diff --git a/Modules/expat/expat_external.h b/Modules/expat/expat_external.h
index cf4d445e68b00c..cc945c424e471f 100644
--- a/Modules/expat/expat_external.h
+++ b/Modules/expat/expat_external.h
@@ -12,9 +12,10 @@
    Copyright (c) 2001-2002 Greg Stein <gstein@users.sourceforge.net>
    Copyright (c) 2002-2006 Karl Waclawek <karl@waclawek.net>
    Copyright (c) 2016      Cristian Rodríguez <crrodriguez@opensuse.org>
-   Copyright (c) 2016-2026 Sebastian Pipping <sebastian@pipping.org>
+   Copyright (c) 2016-2025 Sebastian Pipping <sebastian@pipping.org>
    Copyright (c) 2017      Rhodri James <rhodri@wildebeest.org.uk>
    Copyright (c) 2018      Yury Gribov <tetra2005@gmail.com>
+   Copyright (c) 2026      Matthew Fernandez <matthew.fernandez@gmail.com>
    Licensed under the MIT license:
 
    Permission is  hereby granted,  free of charge,  to any  person obtaining
@@ -48,7 +49,7 @@
 /* Expat tries very hard to make the API boundary very specifically
    defined.  There are two macros defined to control this boundary;
    each of these can be defined before including this header to
-   achieve some different behavior, but doing so it not recommended or
+   achieve some different behavior, but doing so is not recommended or
    tested frequently.
 
    XMLCALL    - The calling convention to use for all calls across the
diff --git a/Modules/expat/internal.h b/Modules/expat/internal.h
index 61266ebb7723d1..420d4217a569b1 100644
--- a/Modules/expat/internal.h
+++ b/Modules/expat/internal.h
@@ -28,7 +28,7 @@
    Copyright (c) 2002-2003 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
    Copyright (c) 2002-2006 Karl Waclawek <karl@waclawek.net>
    Copyright (c) 2003      Greg Stein <gstein@users.sourceforge.net>
-   Copyright (c) 2016-2025 Sebastian Pipping <sebastian@pipping.org>
+   Copyright (c) 2016-2026 Sebastian Pipping <sebastian@pipping.org>
    Copyright (c) 2018      Yury Gribov <tetra2005@gmail.com>
    Copyright (c) 2019      David Loffredo <loffredo@steptools.com>
    Copyright (c) 2023-2024 Sony Corporation / Snild Dolkow <snild@sony.com>
@@ -113,6 +113,7 @@
 #if defined(_WIN32)                                                            \
     && (! defined(__USE_MINGW_ANSI_STDIO)                                      \
         || (1 - __USE_MINGW_ANSI_STDIO - 1 == 0))
+#  define EXPAT_FMT_LLX(midpart) "%" midpart "I64x"
 #  define EXPAT_FMT_ULL(midpart) "%" midpart "I64u"
 #  if defined(_WIN64) // Note: modifiers "td" and "zu" do not work for MinGW
 #    define EXPAT_FMT_PTRDIFF_T(midpart) "%" midpart "I64d"
@@ -122,6 +123,7 @@
 #    define EXPAT_FMT_SIZE_T(midpart) "%" midpart "u"
 #  endif
 #else
+#  define EXPAT_FMT_LLX(midpart) "%" midpart "llx"
 #  define EXPAT_FMT_ULL(midpart) "%" midpart "llu"
 #  if ! defined(ULONG_MAX)
 #    error Compiler did not define ULONG_MAX for us
diff --git a/Modules/expat/refresh.sh b/Modules/expat/refresh.sh
index 779929fc6ed33c..774e0b89d94c0e 100755
--- a/Modules/expat/refresh.sh
+++ b/Modules/expat/refresh.sh
@@ -12,9 +12,9 @@ fi
 
 # Update this when updating to a new version after verifying that the changes
 # the update brings in are good. These values are used for verifying the SBOM, too.
-expected_libexpat_tag="R_2_7_5"
-expected_libexpat_version="2.7.5"
-expected_libexpat_sha256="9931f9860d18e6cf72d183eb8f309bfb96196c00e1d40caa978e95bc9aa978b6"
+expected_libexpat_tag="R_2_8_0"
+expected_libexpat_version="2.8.0"
+expected_libexpat_sha256="c7cec5f60ea3a42e7780781c6745255c19aa3dbfeeae58646b7132f88dc24780"
 
 expat_dir="$(realpath "$(dirname -- "${BASH_SOURCE[0]}")")"
 cd ${expat_dir}
@@ -64,6 +64,18 @@ This may be due to source changes and will require updating this script" >&2
   exit 1
 fi
 
+# Step 4: Skip the Windows rand_s entropy path in xmlparse.c when
+# XML_POOR_ENTROPY is set.
+sed -z -i 's|#if defined(_WIN32)\n#  include "random_rand_s\.h"\n#endif /\* defined(_WIN32) \*/|#if defined(_WIN32) \&\& ! defined(XML_POOR_ENTROPY)\n#  include "random_rand_s.h"\n#endif /* defined(_WIN32) \&\& ! defined(XML_POOR_ENTROPY) */|' xmlparse.c
+sed -z -i 's|#  ifdef _WIN32\n  if (writeRandomBytes_rand_s|#  if defined(_WIN32) \&\& ! defined(XML_POOR_ENTROPY)\n  if (writeRandomBytes_rand_s|' xmlparse.c
+
+if ! grep -q '#if defined(_WIN32) && ! defined(XML_POOR_ENTROPY)' xmlparse.c; then
+  echo "
+Error: rand_s gate not patched in xmlparse.c;
+This may be due to source changes and will require updating this script" >&2
+  exit 1
+fi
+
 echo '
 Updated! next steps:
 - Verify all is okay:
diff --git a/Modules/expat/xmlparse.c b/Modules/expat/xmlparse.c
index 0248b6651ffbff..e6842f3f0bf750 100644
--- a/Modules/expat/xmlparse.c
+++ b/Modules/expat/xmlparse.c
@@ -1,4 +1,4 @@
-/* 93c1caa66e2b0310459482516af05505b57c5cb7b96df777105308fc585c85d1 (2.7.5+)
+/* a5d18f6a50f536615ac1c70304f87d94f99cc85a86b502188952440610ccf0f8 (2.8.0+)
                             __  __            _
                          ___\ \/ /_ __   __ _| |_
                         / _ \\  /| '_ \ / _` | __|
@@ -41,10 +41,12 @@
    Copyright (c) 2023-2024 Sony Corporation / Snild Dolkow <snild@sony.com>
    Copyright (c) 2024-2025 Berkay Eren Ürün <berkay.ueruen@siemens.com>
    Copyright (c) 2024      Hanno Böck <hanno@gentoo.org>
-   Copyright (c) 2025      Matthew Fernandez <matthew.fernandez@gmail.com>
+   Copyright (c) 2025-2026 Matthew Fernandez <matthew.fernandez@gmail.com>
    Copyright (c) 2025      Atrem Borovik <polzovatellllk@gmail.com>
    Copyright (c) 2025      Alfonso Gregory <gfunni234@gmail.com>
    Copyright (c) 2026      Rosen Penev <rosenp@gmail.com>
+   Copyright (c) 2026      Francesco Bertolaccini
+   Copyright (c) 2026      Christian Ng <christianrng@berkeley.edu>
    Licensed under the MIT license:
 
    Permission is  hereby granted,  free of charge,  to any  person obtaining
@@ -84,28 +86,16 @@
 #  error XML_CONTEXT_BYTES must be defined, non-empty and >=0 (0 to disable, >=1 to enable; 1024 is a common default)
 #endif
 
-#if defined(HAVE_SYSCALL_GETRANDOM)
-#  if ! defined(_GNU_SOURCE)
-#    define _GNU_SOURCE 1 /* syscall prototype */
-#  endif
-#endif
-
-#ifdef _WIN32
-/* force stdlib to define rand_s() */
-#  if ! defined(_CRT_RAND_S)
-#    define _CRT_RAND_S
-#  endif
-#endif
-
 #include <stdbool.h>
 #include <stddef.h>
 #include <string.h> /* memset(), memcpy() */
 #include <assert.h>
 #include <limits.h> /* INT_MAX, UINT_MAX */
 #include <stdio.h>  /* fprintf */
-#include <stdlib.h> /* getenv, rand_s */
+#include <stdlib.h> /* getenv */
 #include <stdint.h> /* SIZE_MAX, uintptr_t */
 #include <math.h>   /* isnan */
+#include <errno.h>
 
 #ifdef _WIN32
 #  define getpid GetCurrentProcessId
@@ -125,26 +115,34 @@
 #include "expat.h"
 #include "siphash.h"
 
+#if defined(HAVE_ARC4RANDOM)
+#  include "random_arc4random.h"
+#endif /* defined(HAVE_ARC4RANDOM) */
+
+#if defined(HAVE_ARC4RANDOM_BUF)
+#  include "random_arc4random_buf.h"
+#endif // defined(HAVE_ARC4RANDOM_BUF)
+
+#if defined(XML_DEV_URANDOM)
+#  include "random_dev_urandom.h"
+#endif /* defined(XML_DEV_URANDOM) */
+
+#if defined(HAVE_GETENTROPY)
+#  include "random_getentropy.h"
+#endif // defined(HAVE_GETENTROPY)
+
 #if defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM)
-#  if defined(HAVE_GETRANDOM)
-#    include <sys/random.h> /* getrandom */
-#  else
-#    include <unistd.h>      /* syscall */
-#    include <sys/syscall.h> /* SYS_getrandom */
-#  endif
-#  if ! defined(GRND_NONBLOCK)
-#    define GRND_NONBLOCK 0x0001
-#  endif /* defined(GRND_NONBLOCK) */
-#endif   /* defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM) */
+#  include "random_getrandom.h"
+#endif /* defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM) */
 
-#if defined(_WIN32) && ! defined(LOAD_LIBRARY_SEARCH_SYSTEM32)
-#  define LOAD_LIBRARY_SEARCH_SYSTEM32 0x00000800
-#endif
+#if defined(_WIN32) && ! defined(XML_POOR_ENTROPY)
+#  include "random_rand_s.h"
+#endif /* defined(_WIN32) && ! defined(XML_POOR_ENTROPY) */
 
 #if ! defined(HAVE_GETRANDOM) && ! defined(HAVE_SYSCALL_GETRANDOM)             \
     && ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM)            \
-    && ! defined(XML_DEV_URANDOM) && ! defined(_WIN32)                         \
-    && ! defined(XML_POOR_ENTROPY)
+    && ! defined(HAVE_GETENTROPY) && ! defined(XML_DEV_URANDOM)                \
+    && ! defined(_WIN32) && ! defined(XML_POOR_ENTROPY)
 #  error You do not have support for any sources of high quality entropy \
     enabled.  For end user security, that is probably not what you want. \
     \
@@ -153,10 +151,11 @@
       * Linux >=3.17 + glibc (including <2.25) (syscall SYS_getrandom): HAVE_SYSCALL_GETRANDOM, \
       * BSD / macOS >=10.7 / glibc >=2.36 (arc4random_buf): HAVE_ARC4RANDOM_BUF, \
       * BSD / macOS (including <10.7) / glibc >=2.36 (arc4random): HAVE_ARC4RANDOM, \
+      * BSD / macOS >=10.12 / glibc >=2.25 (getentropy): HAVE_GETENTROPY, \
       * Linux (including <3.17) / BSD / macOS (including <10.7) / Solaris >=8 (/dev/urandom): XML_DEV_URANDOM, \
       * Windows >=Vista (rand_s): _WIN32. \
     \
-    If insist on not using any of these, bypass this error by defining \
+    If you insist on not using any of these, bypass this error by defining \
     XML_POOR_ENTROPY; you have been warned. \
     \
     If you have reasons to patch this detection code away or need changes \
@@ -604,7 +603,7 @@ static ELEMENT_TYPE *getElementType(XML_Parser parser, const ENCODING *enc,
 
 static XML_Char *copyString(const XML_Char *s, XML_Parser parser);
 
-static unsigned long generate_hash_secret_salt(XML_Parser parser);
+static struct sipkey generate_hash_secret_salt(void);
 static XML_Bool startParsing(XML_Parser parser);
 
 static XML_Parser parserCreate(const XML_Char *encodingName,
@@ -777,7 +776,8 @@ struct XML_ParserStruct {
   XML_Bool m_useForeignDTD;
   enum XML_ParamEntityParsing m_paramEntityParsing;
 #endif
-  unsigned long m_hash_secret_salt;
+  struct sipkey m_hash_secret_salt_128;
+  XML_Bool m_hash_secret_salt_set;
 #if XML_GE == 1
   ACCOUNTING m_accounting;
   MALLOC_TRACKER m_alloc_tracker;
@@ -1036,135 +1036,6 @@ static const XML_Char implicitContext[]
        ASCII_s,     ASCII_p,     ASCII_a,      ASCII_c,      ASCII_e,
        '\0'};
 
-/* To avoid warnings about unused functions: */
-#if ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM)
-
-#  if defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM)
-
-/* Obtain entropy on Linux 3.17+ */
-static int
-writeRandomBytes_getrandom_nonblock(void *target, size_t count) {
-  int success = 0; /* full count bytes written? */
-  size_t bytesWrittenTotal = 0;
-  const unsigned int getrandomFlags = GRND_NONBLOCK;
-
-  do {
-    void *const currentTarget = (void *)((char *)target + bytesWrittenTotal);
-    const size_t bytesToWrite = count - bytesWrittenTotal;
-
-    assert(bytesToWrite <= INT_MAX);
-
-    const int bytesWrittenMore =
-#    if defined(HAVE_GETRANDOM)
-        (int)getrandom(currentTarget, bytesToWrite, getrandomFlags);
-#    else
-        (int)syscall(SYS_getrandom, currentTarget, bytesToWrite,
-                     getrandomFlags);
-#    endif
-
-    if (bytesWrittenMore > 0) {
-      bytesWrittenTotal += bytesWrittenMore;
-      if (bytesWrittenTotal >= count)
-        success = 1;
-    }
-  } while (! success && (errno == EINTR));
-
-  return success;
-}
-
-#  endif /* defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM) */
-
-#  if ! defined(_WIN32) && defined(XML_DEV_URANDOM)
-
-/* Extract entropy from /dev/urandom */
-static int
-writeRandomBytes_dev_urandom(void *target, size_t count) {
-  int success = 0; /* full count bytes written? */
-  size_t bytesWrittenTotal = 0;
-
-  const int fd = open("/dev/urandom", O_RDONLY);
-  if (fd < 0) {
-    return 0;
-  }
-
-  do {
-    void *const currentTarget = (void *)((char *)target + bytesWrittenTotal);
-    const size_t bytesToWrite = count - bytesWrittenTotal;
-
-    const ssize_t bytesWrittenMore = read(fd, currentTarget, bytesToWrite);
-
-    if (bytesWrittenMore > 0) {
-      bytesWrittenTotal += bytesWrittenMore;
-      if (bytesWrittenTotal >= count)
-        success = 1;
-    }
-  } while (! success && (errno == EINTR));
-
-  close(fd);
-  return success;
-}
-
-#  endif /* ! defined(_WIN32) && defined(XML_DEV_URANDOM) */
-
-#endif /* ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM) */
-
-#if defined(HAVE_ARC4RANDOM) && ! defined(HAVE_ARC4RANDOM_BUF)
-
-static void
-writeRandomBytes_arc4random(void *target, size_t count) {
-  size_t bytesWrittenTotal = 0;
-
-  while (bytesWrittenTotal < count) {
-    const uint32_t random32 = arc4random();
-    size_t i = 0;
-
-    for (; (i < sizeof(random32)) && (bytesWrittenTotal < count);
-         i++, bytesWrittenTotal++) {
-      const uint8_t random8 = (uint8_t)(random32 >> (i * 8));
-      ((uint8_t *)target)[bytesWrittenTotal] = random8;
-    }
-  }
-}
-
-#endif /* defined(HAVE_ARC4RANDOM) && ! defined(HAVE_ARC4RANDOM_BUF) */
-
-#ifdef _WIN32
-
-/* Provide declaration of rand_s() for MinGW-32 (not 64, which has it),
-   as it didn't declare it in its header prior to version 5.3.0 of its
-   runtime package (mingwrt, containing stdlib.h).  The upstream fix
-   was introduced at https://osdn.net/projects/mingw/ticket/39658 . */
-#  if defined(__MINGW32__) && defined(__MINGW32_VERSION)                       \
-      && __MINGW32_VERSION < 5003000L && ! defined(__MINGW64_VERSION_MAJOR)
-__declspec(dllimport) int rand_s(unsigned int *);
-#  endif
-
-/* Obtain entropy on Windows using the rand_s() function which
- * generates cryptographically secure random numbers.  Internally it
- * uses RtlGenRandom API which is present in Windows XP and later.
- */
-static int
-writeRandomBytes_rand_s(void *target, size_t count) {
-  size_t bytesWrittenTotal = 0;
-
-  while (bytesWrittenTotal < count) {
-    unsigned int random32 = 0;
-    size_t i = 0;
-
-    if (rand_s(&random32))
-      return 0; /* failure */
-
-    for (; (i < sizeof(random32)) && (bytesWrittenTotal < count);
-         i++, bytesWrittenTotal++) {
-      const uint8_t random8 = (uint8_t)(random32 >> (i * 8));
-      ((uint8_t *)target)[bytesWrittenTotal] = random8;
-    }
-  }
-  return 1; /* success */
-}
-
-#endif /* _WIN32 */
-
 #if ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM)
 
 static unsigned long
@@ -1192,69 +1063,70 @@ gather_time_entropy(void) {
 
 #endif /* ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM) */
 
-static unsigned long
-ENTROPY_DEBUG(const char *label, unsigned long entropy) {
+static struct sipkey
+ENTROPY_DEBUG(const char *label, struct sipkey entropy_128) {
   if (getDebugLevel("EXPAT_ENTROPY_DEBUG", 0) >= 1u) {
-    fprintf(stderr, "expat: Entropy: %s --> 0x%0*lx (%lu bytes)\n", label,
-            (int)sizeof(entropy) * 2, entropy, (unsigned long)sizeof(entropy));
+    fprintf(stderr,
+            "expat: Entropy: %s --> [0x" EXPAT_FMT_LLX(
+                "016") ", 0x" EXPAT_FMT_LLX("016") "] (16 bytes)\n",
+            label, (unsigned long long)entropy_128.k[0],
+            (unsigned long long)entropy_128.k[1]);
   }
-  return entropy;
+  return entropy_128;
 }
 
-static unsigned long
-generate_hash_secret_salt(XML_Parser parser) {
-  unsigned long entropy;
-  (void)parser;
+static struct sipkey
+generate_hash_secret_salt(void) {
+  struct sipkey entropy;
 
   /* "Failproof" high quality providers: */
 #if defined(HAVE_ARC4RANDOM_BUF)
-  arc4random_buf(&entropy, sizeof(entropy));
+  writeRandomBytes_arc4random_buf(&entropy, sizeof(entropy));
   return ENTROPY_DEBUG("arc4random_buf", entropy);
 #elif defined(HAVE_ARC4RANDOM)
-  writeRandomBytes_arc4random((void *)&entropy, sizeof(entropy));
+  writeRandomBytes_arc4random(&entropy, sizeof(entropy));
   return ENTROPY_DEBUG("arc4random", entropy);
 #else
   /* Try high quality providers first .. */
-#  ifdef _WIN32
-  if (writeRandomBytes_rand_s((void *)&entropy, sizeof(entropy))) {
+#  if defined(_WIN32) && ! defined(XML_POOR_ENTROPY)
+  if (writeRandomBytes_rand_s(&entropy, sizeof(entropy))) {
     return ENTROPY_DEBUG("rand_s", entropy);
   }
+#  elif defined(HAVE_GETENTROPY)
+  if (writeRandomBytes_getentropy(&entropy, sizeof(entropy))) {
+    return ENTROPY_DEBUG("getentropy", entropy);
+  }
+  errno = 0;
 #  elif defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM)
-  if (writeRandomBytes_getrandom_nonblock((void *)&entropy, sizeof(entropy))) {
+  if (writeRandomBytes_getrandom_nonblock(&entropy, sizeof(entropy))) {
     return ENTROPY_DEBUG("getrandom", entropy);
   }
 #  endif
 #  if ! defined(_WIN32) && defined(XML_DEV_URANDOM)
-  if (writeRandomBytes_dev_urandom((void *)&entropy, sizeof(entropy))) {
+  if (writeRandomBytes_dev_urandom(&entropy, sizeof(entropy))) {
     return ENTROPY_DEBUG("/dev/urandom", entropy);
   }
 #  endif /* ! defined(_WIN32) && defined(XML_DEV_URANDOM) */
   /* .. and self-made low quality for backup: */
 
-  entropy = gather_time_entropy();
+  entropy.k[0] = 0;
+  entropy.k[1] = gather_time_entropy();
 #  if ! defined(__wasi__)
   /* Process ID is 0 bits entropy if attacker has local access */
-  entropy ^= getpid();
+  entropy.k[1] ^= getpid();
 #  endif
 
   /* Factors are 2^31-1 and 2^61-1 (Mersenne primes M31 and M61) */
   if (sizeof(unsigned long) == 4) {
-    return ENTROPY_DEBUG("fallback(4)", entropy * 2147483647);
+    entropy.k[1] *= 2147483647;
+    return ENTROPY_DEBUG("fallback(4)", entropy);
   } else {
-    return ENTROPY_DEBUG("fallback(8)",
-                         entropy * (unsigned long)2305843009213693951ULL);
+    entropy.k[1] *= 2305843009213693951ULL;
+    return ENTROPY_DEBUG("fallback(8)", entropy);
   }
 #endif
 }
 
-static unsigned long
-get_hash_secret_salt(XML_Parser parser) {
-  const XML_Parser rootParser = getRootParserOf(parser, NULL);
-  assert(! rootParser->m_parentParser);
-
-  return rootParser->m_hash_secret_salt;
-}
-
 static enum XML_Error
 callProcessor(XML_Parser parser, const char *start, const char *end,
               const char **endPtr) {
@@ -1323,8 +1195,10 @@ callProcessor(XML_Parser parser, const char *start, const char *end,
 static XML_Bool /* only valid for root parser */
 startParsing(XML_Parser parser) {
   /* hash functions must be initialized before setContext() is called */
-  if (parser->m_hash_secret_salt == 0)
-    parser->m_hash_secret_salt = generate_hash_secret_salt(parser);
+  if (parser->m_hash_secret_salt_set != XML_TRUE) {
+    parser->m_hash_secret_salt_128 = generate_hash_secret_salt();
+    parser->m_hash_secret_salt_set = XML_TRUE;
+  }
   if (parser->m_ns) {
     /* implicit context only set for root parser, since child
        parsers (i.e. external entity parsers) will inherit it
@@ -1612,7 +1486,9 @@ parserInit(XML_Parser parser, const XML_Char *encodingName) {
   parser->m_useForeignDTD = XML_FALSE;
   parser->m_paramEntityParsing = XML_PARAM_ENTITY_PARSING_NEVER;
 #endif
-  parser->m_hash_secret_salt = 0;
+  parser->m_hash_secret_salt_128.k[0] = 0;
+  parser->m_hash_secret_salt_128.k[1] = 0;
+  parser->m_hash_secret_salt_set = XML_FALSE;
 
 #if XML_GE == 1
   memset(&parser->m_accounting, 0, sizeof(ACCOUNTING));
@@ -1779,7 +1655,8 @@ XML_ExternalEntityParserCreate(XML_Parser oldParser, const XML_Char *context,
      from hash tables associated with either parser without us having
      to worry which hash secrets each table has.
   */
-  unsigned long oldhash_secret_salt;
+  struct sipkey oldhash_secret_salt_128;
+  XML_Bool oldhash_secret_salt_set;
   XML_Bool oldReparseDeferralEnabled;
 
   /* Validate the oldParser parameter before we pull everything out of it */
@@ -1825,7 +1702,8 @@ XML_ExternalEntityParserCreate(XML_Parser oldParser, const XML_Char *context,
      from hash tables associated with either parser without us having
      to worry which hash secrets each table has.
   */
-  oldhash_secret_salt = parser->m_hash_secret_salt;
+  oldhash_secret_salt_128 = parser->m_hash_secret_salt_128;
+  oldhash_secret_salt_set = parser->m_hash_secret_salt_set;
   oldReparseDeferralEnabled = parser->m_reparseDeferralEnabled;
 
 #ifdef XML_DTD
@@ -1880,7 +1758,8 @@ XML_ExternalEntityParserCreate(XML_Parser oldParser, const XML_Char *context,
     parser->m_externalEntityRefHandlerArg = oldExternalEntityRefHandlerArg;
   parser->m_defaultExpandInternalEntities = oldDefaultExpandInternalEntities;
   parser->m_ns_triplets = oldns_triplets;
-  parser->m_hash_secret_salt = oldhash_secret_salt;
+  parser->m_hash_secret_salt_128 = oldhash_secret_salt_128;
+  parser->m_hash_secret_salt_set = oldhash_secret_salt_set;
   parser->m_reparseDeferralEnabled = oldReparseDeferralEnabled;
   parser->m_parentParser = oldParser;
 #ifdef XML_DTD
@@ -2324,6 +2203,7 @@ XML_SetParamEntityParsing(XML_Parser parser,
 #endif
 }
 
+// DEPRECATED since Expat 2.8.0.
 int XMLCALL
 XML_SetHashSalt(XML_Parser parser, unsigned long hash_salt) {
   if (parser == NULL)
@@ -2335,10 +2215,46 @@ XML_SetHashSalt(XML_Parser parser, unsigned long hash_salt) {
   /* block after XML_Parse()/XML_ParseBuffer() has been called */
   if (parserBusy(rootParser))
     return 0;
-  rootParser->m_hash_secret_salt = hash_salt;
+
+  rootParser->m_hash_secret_salt_128.k[0] = 0;
+  rootParser->m_hash_secret_salt_128.k[1] = hash_salt;
+
+  if (hash_salt != 0) { // to remain backwards compatible
+    rootParser->m_hash_secret_salt_set = XML_TRUE;
+
+    if (sizeof(unsigned long) == 4)
+      ENTROPY_DEBUG("explicit(4)", rootParser->m_hash_secret_salt_128);
+    else
+      ENTROPY_DEBUG("explicit(8)", rootParser->m_hash_secret_salt_128);
+  }
+
   return 1;
 }
 
+XML_Bool XMLCALL
+XML_SetHashSalt16Bytes(XML_Parser parser, const uint8_t entropy[16]) {
+  if (parser == NULL)
+    return XML_FALSE;
+
+  if (entropy == NULL)
+    return XML_FALSE;
+
+  const XML_Parser rootParser = getRootParserOf(parser, NULL);
+  assert(! rootParser->m_parentParser);
+
+  /* block after XML_Parse()/XML_ParseBuffer() has been called */
+  if (parserBusy(rootParser))
+    return XML_FALSE;
+
+  sip_tokey(&(rootParser->m_hash_secret_salt_128), entropy);
+
+  rootParser->m_hash_secret_salt_set = XML_TRUE;
+
+  ENTROPY_DEBUG("explicit(16)", rootParser->m_hash_secret_salt_128);
+
+  return XML_TRUE;
+}
+
 enum XML_Status XMLCALL
 XML_Parse(XML_Parser parser, const char *s, int len, int isFinal) {
   if ((parser == NULL) || (len < 0) || ((s == NULL) && (len != 0))) {
@@ -7842,8 +7758,10 @@ keylen(KEY s) {
 
 static void
 copy_salt_to_sipkey(XML_Parser parser, struct sipkey *key) {
-  key->k[0] = 0;
-  key->k[1] = get_hash_secret_salt(parser);
+  const XML_Parser rootParser = getRootParserOf(parser, NULL);
+  assert(! rootParser->m_parentParser);
+
+  *key = rootParser->m_hash_secret_salt_128;
 }
 
 static unsigned long FASTCALL
diff --git a/Modules/expat/xmlrole.c b/Modules/expat/xmlrole.c
index b1dfb456e5df87..d56bee82dd2d13 100644
--- a/Modules/expat/xmlrole.c
+++ b/Modules/expat/xmlrole.c
@@ -12,7 +12,7 @@
    Copyright (c) 2002-2006 Karl Waclawek <karl@waclawek.net>
    Copyright (c) 2002-2003 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
    Copyright (c) 2005-2009 Steven Solie <steven@solie.ca>
-   Copyright (c) 2016-2026 Sebastian Pipping <sebastian@pipping.org>
+   Copyright (c) 2016-2023 Sebastian Pipping <sebastian@pipping.org>
    Copyright (c) 2017      Rhodri James <rhodri@wildebeest.org.uk>
    Copyright (c) 2019      David Loffredo <loffredo@steptools.com>
    Copyright (c) 2021      Donghee Na <donghee.na@python.org>
diff --git a/Modules/expat/xmltok.c b/Modules/expat/xmltok.c
index f6e5f742c928c8..32cd5f147e9322 100644
--- a/Modules/expat/xmltok.c
+++ b/Modules/expat/xmltok.c
@@ -12,7 +12,7 @@
    Copyright (c) 2002      Greg Stein <gstein@users.sourceforge.net>
    Copyright (c) 2002-2016 Karl Waclawek <karl@waclawek.net>
    Copyright (c) 2005-2009 Steven Solie <steven@solie.ca>
-   Copyright (c) 2016-2026 Sebastian Pipping <sebastian@pipping.org>
+   Copyright (c) 2016-2024 Sebastian Pipping <sebastian@pipping.org>
    Copyright (c) 2016      Pascal Cuoq <cuoq@trust-in-soft.com>
    Copyright (c) 2016      Don Lewis <truckman@apache.org>
    Copyright (c) 2017      Rhodri James <rhodri@wildebeest.org.uk>
diff --git a/Modules/expat/xmltok_ns.c b/Modules/expat/xmltok_ns.c
index 1cd60de1e4fe51..810ca2c6d0485e 100644
--- a/Modules/expat/xmltok_ns.c
+++ b/Modules/expat/xmltok_ns.c
@@ -11,7 +11,7 @@
    Copyright (c) 2002      Greg Stein <gstein@users.sourceforge.net>
    Copyright (c) 2002      Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
    Copyright (c) 2002-2006 Karl Waclawek <karl@waclawek.net>
-   Copyright (c) 2017-2026 Sebastian Pipping <sebastian@pipping.org>
+   Copyright (c) 2017-2021 Sebastian Pipping <sebastian@pipping.org>
    Copyright (c) 2025      Alfonso Gregory <gfunni234@gmail.com>
    Licensed under the MIT license: