CVE-2026-120439
CVE-2026-120439
QuickJS-NG before 0.16.0 contains an integer overflow in js_typed_array_sort() in quickjs.c that allows attackers to cause a heap buffer overflow on 32-bit hosts. Attackers who can run JavaScript can call TypedArray.prototype.sort with a comparator on a typed array near 2^30 elements, wrapping the allocation size and writing indices past the buffer to crash or potentially execute code.
Vulnerability class: Integer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Weakness classification (CWE)
References
- github.com/quickjs-ng/quickjs/security/advisories/GHSA-9wv5-5cgr-grj6 (vendor-advisory)
- github.com/quickjs-ng/quickjs/commit/e93cca611908e12b824ec85fbee6b31a5ee61568 (patch)
- github.com/quickjs-ng/quickjs/releases/tag/v0.16.0 (release-notes)
- github.com/quickjs-ng/quickjs/blob/v0.15.1/quickjs.c (technical-description)
- www.vulncheck.com/advisories/quickjs-ng-before-0.16.0-heap-buffer-overflow-via-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-120439?
- CVE-2026-120439 is a high-severity vulnerability, classified under Integer Overflow or Wraparound. CVSS score: 7.0/10. Published 2026-11-02.
- How severe is CVE-2026-120439?
- High severity. CVSS v3 base score is 7.0 out of 10.