CVE-2026-18477
Full vulnerability record from the local CVENow database.
Description
A TOCTOU (Time-of-Check Time-of-Use) vulnerability in GNU tar's incremental dumpdir 'X' rename handling allows a local attacker with write access to a directory being backed up to influence the restore process if the attacker has access to the system where the restore is being performed. During restoration, files or directories may be created, renamed or overwritten outside the intended extraction directory. This could lead to unauthorized file modification or, in some cases, privilege escalation. Exploitation does not require the attacker to modify or craft the archive, and standard backup and restore workflows—including extracting into a newly created directory without using the -P option do not mitigate the issue.
Severity
MEDIUM
CVSS score
4.4
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-08-03 17:16:33.897000
Last modified
2026-10-30 19:18:23.100000
View original CVE JSON
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"sourceIdentifier": "[email protected]",
"published": "2026-08-03T17:16:33.897",
"lastModified": "2026-10-30T19:18:23.100",
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