CVE-2026-66485

Uncontrolled Memory Allocation in GNU cpio

MEDIUM
4.6
CVSS Score
Published: August 10, 2026 at 10:25 AM UTC
Updated: October 24, 2026 at 04:10 PM UTC
1 product affected across 1 vendorCpio

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Severity
MEDIUM4.6
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

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

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0 ≤ v ≤ 2.150

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (2)

Third Party Advisory
Source: cverecord
https://cert.pl/en/posts/2026/08/CVE-2026-66484

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.6MEDIUMCERT-PL
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-789

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