VulnerabilityDeferred

CVE-2026-66484

GNU cpio contains a Path Traversal vulnerability in its tar archive extraction functionality.

MEDIUM 4.6EPSS 0.16%

Does this matter?

Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own.

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

CVSS 4.0: 4.6 MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.16% probability · 5th percentile
CISA KEV: Not listed
Weakness: CWE-22
Source: cvd@cert.pl

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.