diff --git a/packages/datasource-customizer/src/decorators/binary/collection.ts b/packages/datasource-customizer/src/decorators/binary/collection.ts
index 2f8652acbc..b1e17dedb5 100644
--- a/packages/datasource-customizer/src/decorators/binary/collection.ts
+++ b/packages/datasource-customizer/src/decorators/binary/collection.ts
@@ -16,7 +16,13 @@ import type {
   RecordData,
 } from '@forestadmin/datasource-toolkit';
 
-import { CollectionDecorator, SchemaUtils, TypeGetter } from '@forestadmin/datasource-toolkit';
+import {
+  CollectionDecorator,
+  SchemaUtils,
+  TypeGetter,
+  ValidationError,
+  parseDataUri,
+} from '@forestadmin/datasource-toolkit';
 import { filetypemime } from 'magic-bytes.js';
 
 /**
@@ -237,15 +243,31 @@ export default class BinaryCollectionDecorator extends CollectionDecorator {
     return value;
   }
 
+  private parseHex(value: string): Buffer {
+    if (!/^([0-9a-f]{2})*$/i.test(value)) {
+      throw new ValidationError(
+        `Expected an even-length hex string for a binary field, got "${value}"`,
+      );
+    }
+
+    return Buffer.from(value, 'hex');
+  }
+
   private async convertScalar(
     toBackend: boolean,
     useHex: boolean,
     value: unknown,
   ): Promise<unknown> {
     if (toBackend) {
-      const string = value as string;
+      if (typeof value !== 'string') {
+        throw new ValidationError(
+          `Expected a string for a binary field, got ${typeof value}: ${JSON.stringify(value)}`,
+        );
+      }
+
+      if (useHex) return this.parseHex(value);
 
-      return useHex ? Buffer.from(string, 'hex') : Buffer.from(string.split(',')[1], 'base64');
+      return parseDataUri(value).buffer;
     }
 
     const buffer = value as Buffer;
diff --git a/packages/datasource-customizer/test/decorators/binary/collection.test.ts b/packages/datasource-customizer/test/decorators/binary/collection.test.ts
index 5c773ec2a3..99afb9cb84 100644
--- a/packages/datasource-customizer/test/decorators/binary/collection.test.ts
+++ b/packages/datasource-customizer/test/decorators/binary/collection.test.ts
@@ -8,6 +8,7 @@ import {
   Filter,
   PaginatedFilter,
   Projection,
+  ValidationError,
 } from '@forestadmin/datasource-toolkit';
 import * as factories from '@forestadmin/datasource-toolkit/dist/test/__factories__';
 
@@ -238,6 +239,66 @@ describe('BinaryCollectionDecorator', () => {
     });
   });
 
+  describe('list filtering a binary column with a value that is not a data uri', () => {
+    it('should reject the filter instead of crashing on an undefined base64 payload', async () => {
+      const caller = factories.caller.build();
+      const filter = new PaginatedFilter({
+        conditionTree: new ConditionTreeLeaf('cover', 'Equal', 'Anthony'),
+      });
+
+      await expect(decoratedBook.list(caller, filter, new Projection('id'))).rejects.toThrow(
+        ValidationError,
+      );
+      expect(books.list).not.toHaveBeenCalled();
+    });
+
+    it('should reject a data uri that is not base64, rather than decode it to garbage', async () => {
+      const caller = factories.caller.build();
+      const filter = new PaginatedFilter({
+        conditionTree: new ConditionTreeLeaf('cover', 'Equal', 'data:text/plain,hello'),
+      });
+
+      await expect(decoratedBook.list(caller, filter, new Projection('id'))).rejects.toThrow(
+        /must be a data uri/,
+      );
+      expect(books.list).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('list filtering a hex binary column with a value that is not hex', () => {
+    it('should reject it rather than query for an empty buffer', async () => {
+      const caller = factories.caller.build();
+      const filter = new PaginatedFilter({
+        conditionTree: new ConditionTreeLeaf('id', 'Equal', 'Anthony'),
+      });
+
+      await expect(decoratedBook.list(caller, filter, new Projection('id'))).rejects.toThrow(
+        /even-length hex string/,
+      );
+      expect(books.list).not.toHaveBeenCalled();
+    });
+
+    it('should reject an odd-length hex string, which silently drops its last digit', async () => {
+      const caller = factories.caller.build();
+      const filter = new PaginatedFilter({
+        conditionTree: new ConditionTreeLeaf('id', 'Equal', '303'),
+      });
+
+      await expect(decoratedBook.list(caller, filter, new Projection('id'))).rejects.toThrow(
+        /even-length hex string/,
+      );
+    });
+  });
+
+  describe('writing a non-string value into a binary column', () => {
+    it('should reject it with a validation error rather than an opaque TypeError', async () => {
+      const caller = factories.caller.build();
+
+      await expect(decoratedBook.create(caller, [{ cover: 42 }])).rejects.toThrow(ValidationError);
+      expect(books.create).not.toHaveBeenCalled();
+    });
+  });
+
   describe('list with a more complex filter', () => {
     // Build condition tree (30303030 is the hex representation of 0000)
     const conditionTree = new ConditionTreeBranch('Or', [