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Fencer Intel
high 7.0

CVE-2026-120439 json

QuickJS-NG before 0.16.0 Heap Buffer Overflow via TypedArray.prototype.sort

published 7d ago modified 3d ago also EUVD-2026-115199

cvss
7.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 28%
public exploits
0
none known

Summary

QuickJS-NG before 0.16.0 contains an integer overflow in js_typed_array_sort() in quickjs.c that allows attackers to cause a heap buffer overflow on 32-bit hosts. Attackers who can run JavaScript can call TypedArray.prototype.sort with a comparator on a typed array near 2^30 elements, wrapping the allocation size and writing indices past the buffer to crash or potentially execute code.

Patch / fix

  • quickjs-ng QuickJS-NG 0.16.0
  • quickjs-ng Debian 14 0.16.2-1

debian advisories DEBIAN-CVE-2026-120439

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3d ago

Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/quickjs-ng/quickjs/security/advisories/GHSA-9wv5-5cgr-grj6 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 8.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
CNA 3.1 7.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
CNA 4.0 8.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/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

Affected products

  • quickjs-ng QuickJS-NG

Classification

Weakness
  • CWE-190 Integer Overflow or Wraparound

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.