CVE-2026-120440: quickjs-ng QuickJS-NG

QuickJS-NG before 0.16.0 Memory Leak via Atomics.store

CVSS 6.9 MediumEPSS 0.0047 · 40th percentile

Published by the CVE Program (CNA: VulnCheck) at 2 Nov 2026, 14:29 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
quickjs-ng	QuickJS-NG pkg:github/quickjs-ng/quickjs	affected before 0.16.0 semver Other versions: unaffected

Identifiers

CVE-2026-120440

CNA

VulnCheck

Weakness (CWE)

CWE-401

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.9	Medium	4.0	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N	CNA (VulnCheck)Used for this record
5.3	Medium	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L	CNA (VulnCheck)

CISA KEV Not listed.
EPSS 0.0047, the 40th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

2 Nov 2026, 14:29 UTC Confirmed by the CVE List
2 Nov 2026, 14:37 UTC First seen by agentprime
2 Nov 2026, 15:17 UTC Confirmed by NVD

Sources

References from the CNA

github.com/quickjs-ng/quickjs/security/advisories/GHSA-wm7w-r6qf-3c9w vendor-advisory
github.com/quickjs-ng/quickjs/commit/62951e1bc68711d37aad986ff84ef0fe17038a7e patch
github.com/quickjs-ng/quickjs/releases/tag/v0.16.0 release-notes
github.com/quickjs-ng/quickjs/blob/v0.15.1/quickjs.c#L61154 technical-description
www.vulncheck.com/advisories/quickjs-ng-before-0.16.0-memory-leak-via-atomics-store third-party-advisory

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.