CVE-2026-66484
Path Traversal in GNU cpio
- State
- Published
- Severity
- 4.6 Medium
- Published
- Aug 10, 2026
- Updated
- Aug 10, 2026
- Reserved
- Jul 27, 2026
Description
GNU cpio contains a Path Traversal vulnerability in its tar archive extraction functionality. When extracting a tar archive in copy-in mode with the --no-absolute-filenames option, the extracted file name is normalized but the tar hard-link target is passed to the link_to_name function without equivalent sanitization before calling link function. A tar archive provided by an attacker, containing a hard-link entry whose linkname is set to an absolute path outside the extraction directory, can cause cpio to create a hard link to an existing file outside the intended extraction directory, breaking the expected guarantee of --no-absolute-filenames and allowing archive-controlled linkage to external files.
This issue has been fixed in commit e2b9cbdd3354d2b1569b7390d1bc15c1930559ad
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 4.6 Medium | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N | CERT-PL |
Weaknesses
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Products
| Product | Versions |
|---|---|
cpioGNU |
|
References
- https://cert.pl/en/posts/2026/08/CVE-2026-66484third-party-advisory
- https://git.savannah.gnu.org/cgit/cpio.gitproduct
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.