CVE-2026-66484

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

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/08/CVE-2026-66484
https://git.savannah.gnu.org/cgit/cpio.git

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 11:17

Updated : 2026-08-28 15:26

NVD link : CVE-2026-66484

Mitre link : CVE-2026-66484

CVE.ORG link : CVE-2026-66484

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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