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CVE-2026-120440

6.9 mediumEPSS 0.5%

Medium (6.9). EPSS 0.5% estimated probability of exploitation activity in the next 30 days.

On this page
QuickJS-NG before 0.16.0 contains a memory leak vulnerability in js_atomics_store() in quickjs.c that fails to free the converted value when returning a RangeError. Attackers running JavaScript can repeatedly call Atomics.store with a valueOf that detaches or shrinks the buffer to exhaust heap memory and cause denial of service.

Severity

CVSS 4.0

6.9 medium
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

CVSS 3.1

5.3 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
0.5% estimated probability of exploitation activity in the next 30 days; 41st percentile. Scored 2026-11-03. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-401 Missing Release of Memory after Effective Lifetime
Published
Modified
Record from
the NVD, synced

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Linux distributions

DistributionReleasePackageFixed inAdvisory
Ubuntu26.10quickjs-ngno fix listedUBUNTU-CVE-2026-120440

From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.

References

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