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...

Description

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 and may be used. Patch name: daab4ad4bae4ef071ed0294618d6244e92def4cd. Applying a patch is the recommended action to fix this issue.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

CVSS 4.0

1.9/10

CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.11%

1.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published: Mar 12, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is 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 and may be used. Patch name: daab4ad4bae4ef071ed0294618d6244e92def4cd. Applying a patch is the recommended action to fix this issue.

How severe is CVE-2026-3979?

CVE-2026-3979 has a CVSS score of 1.9/10 (LOW severity). The EPSS model estimates a 0.11% probability of exploitation in the next 30 days.

How do I fix CVE-2026-3979?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.