PatchTheCVECVE-2026-66486: GNU cpio is vulnerable to improper encoding or escaping of output in its archive member listing functionality
18
Routine
MEDIUM 4.6
CVE-2026-66486 is a medium-severity flaw (CVSS 4.6) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- No elevated risk signals yet
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 4.6 (Medium) |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Active |
| EPSS exploit chance | 0.2% (top 92%) |
| CISA exploited list | No |
| Weakness | CWE-116 |
| Published | 2026-08-10 |
| Last modified | 2026-10-23 |
Publisher (CNA): CERT.PL
Timeline
- Published CVE record published
- Updated Record last modified
Advisories and coverage
Official advisories
- CERT Polska: Vulnerabilities in GNU cpio software 2026-08-10
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.