Vulnerability · Published Sep 24, 2026 · Assigned by mitre
CVE-2026-88378
Critical 9.8
In plain English
A critical-severity out-of-bounds write in the quickjs package (Debian). Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities).
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.6%top 53.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
QuickJS commit 04be24600 contains a heap out-of-bounds write condition in JS_ReadFunctionTag().
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | quickjs | no fix listed | DEBIAN-CVE-2026-88378 |
| Debian:14 | quickjs | no fix listed | DEBIAN-CVE-2026-88378 |
| Debian:14 | quickjs-ng | no fix listed | DEBIAN-CVE-2026-88378 |
| Ubuntu:26.04:LTS | quickjs | no fix listed | UBUNTU-CVE-2026-88378 |
| Ubuntu:26.10 | quickjs | no fix listed | UBUNTU-CVE-2026-88378 |
Affected products (as reported)
Weakness: CWE-787 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H