Kysely is a type-safe TypeScript SQL query builder. From 0.26.0 to 0.28.16, DefaultQueryCompiler.visitJSONPathLeg does not escape JSON-path metacharacters (., [, ], *, **, ?). When attacker-controlled input flows into eb.ref(col, '->$').key(input) or .at(input) — including type-safe code where the JSON column is shaped like Record<string, T> so K extends string is the inferred type — every dot becomes a path-leg separator, letting an attacker traverse from the intended key into sibling and child fields the developer never meant to expose. The result is read access (and, in update statements, write access) to JSON sub-fields outside the intended scope across MySQL, PostgreSQL ->$/->>$, and SQLite. This vulnerability is fixed in 0.28.17.

Kysely is a type-safe TypeScript SQL query builder. Prior to version 0.28.14, 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()`. Version 0.28.14 contains a fix.

Kysely is a type-safe TypeScript SQL query builder. In versions 0.28.12 and 0.28.13, the `sanitizeStringLiteral` method in Kysely's query compiler escapes single quotes (`'` → `''`) but does not escape backslashes. On MySQL with the default `BACKSLASH_ESCAPES` SQL mode, an attacker can inject a backslash before a single quote to neutralize the escaping, breaking out of the JSON path string literal and injecting arbitrary SQL. Version 0.28.14 fixes the issue.

Kysely is a type-safe TypeScript SQL query builder. Versions up to and including 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. Version 0.28.12 fixes the issue.