CVE intelligence

CVE-2026-66486

Vulnerability intelligence

Published Aug 10, 2026Sources checked Oct 28, 2026

4.6MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-66486 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-2026-66486?

GNU cpio is vulnerable to improper encoding or escaping of output in its archive member listing functionality. When listing archive members via cpio -it, member names are printed directly to output without quoting or escaping.

An attacker can craft a cpio archive containing member names with embedded newline characters or ANSI escape sequences, causing forged listing entries or terminal control sequence injection when the listing is displayed.

This issue has been fixed in commit 2ff9600c9ef32e88759843cdbde74c8db5ae9b30

Source: NVD