CVE intelligence

CVE-2026-66485

Vulnerability intelligence

Published Aug 10, 2026Sources checked Oct 28, 2026

4.6MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-66485 and is rated Medium severity with a CVSS score of 4.6. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 13, 2026

See the Microsoft Security Update Guide for the update that applies to your product.

Vendor-listed releases

2.14-2

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-66485?

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

Source: NVD