CVE-2026-120440

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/quickjs-ng/quickjs/blob/v0.15.1/quickjs.c#L61154
https://github.com/quickjs-ng/quickjs/commit/62951e1bc68711d37aad986ff84ef0fe17038a7e
https://github.com/quickjs-ng/quickjs/releases/tag/v0.16.0
https://github.com/quickjs-ng/quickjs/security/advisories/GHSA-wm7w-r6qf-3c9w
https://www.vulncheck.com/advisories/quickjs-ng-before-0.16.0-memory-leak-via-atomics-store

Configurations

No configuration.

History

02 Nov 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-11-02 15:17

Updated : 2026-11-02 19:34

NVD link : CVE-2026-120440

Mitre link : CVE-2026-120440

CVE.ORG link : CVE-2026-120440

JSON object : View

Products Affected

No product.

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

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