Kysely has a MySQL SQL Injection via Insufficient Backslash Escaping in `sql.lit(string)` usage or similar methods that append string literal values into the compiled SQL strings

published 2026-03-20 7 mo ago modified 2026-09-10 1 mo ago also GHSA-8cpq-38p9-67gx , EUVD-2026-16265

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits: 0; none known

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.

Patch / fix

fixed in 2

npm kysely 0.28.14
kysely kysely 0.28.14

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 7 mo ago (2026-03-26)

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/kysely-org/kysely/security/advisories/GHSA-8cpq-38p9-67gx referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
GitHub	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
npm	kysely	<0.28.14	0.28.14

Affected products

kysely-org kysely

Classification

Weakness

CWE-89 Improper Neutralization of Special Elements used in an SQL Command

References

github.com /kysely-org/kysely/security/advisories/GHSA-8cpq-38p9-67gx
web, exploit, mitigation, vendor-advisory
nvd.nist.gov /vuln/detail/CVE-2026-33468
advisory
github.com /kysely-org/kysely
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary