CVE-2026-66485

Publication date 10 August 2026

Last updated 18 August 2026


Ubuntu priority

Description

GNU cpio is vulnerable to an uncontrolled memory allocation in the make_path function at src/makepath.c. The function uses alloca to allocate stack memory based on the length of argpath, which is derived from an archive-controlled pathname during extraction. A malicious cpio archive containing a sufficiently long nested pathname causes an unbounded stack allocation, resulting in a stack overflow and crash of the cpio process. An attacker who can supply a crafted cpio archive to a victim who extracts it can cause a denial of service. This issue has been fixed in commit 3cd514031371d8aeeaf2048aa10103e02831aaa9

Status

Package Ubuntu Release Status
cpio 26.04 LTS resolute
Vulnerable
24.04 LTS noble
Vulnerable
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Vulnerable

Patch details

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Package Patch details
cpio

Severity score breakdown

CVSS version: CVSS v4.0

Base score 4.6 · Medium

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N


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