Buffer overflow in Quickjs-ng Quickjs

CVE-2026-3979

A flaw has been found in quickjs-ng quickjs up to 0.12.1. This affects the function js_iterator_concat_return of the file quickjs.c. This manipulation causes use after free. The attack requires local access. The exploit has been published…

Vulnerability class: Buffer Overflow

EPSS: 0.000 (5.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3979?
CVE-2026-3979 is a medium-severity vulnerability in Quickjs-ng Quickjs, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.3/10. Published 2026-03-12.
How severe is CVE-2026-3979?
Medium severity. CVSS v3 base score is 5.3 out of 10.