CVE-2026-18508
Full vulnerability record from the local CVENow database.
Description
A flaw was found in GNU tar. When extracting an archive with the --one-top-level option, hardlink targets are not confined to the designated top-level directory and may resolve relative to the extraction working directory. A crafted archive can create hardlinks that escape the intended boundary and, when combined with a preexisting symbolic link under the working directory, may allow writing outside that boundary during a single extraction.
Severity
MEDIUM
CVSS score
4.4
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-08-03 16:16:28.387000
Last modified
2026-10-30 13:18:33.020000
View original CVE JSON
{
"id": "CVE-2026-18508",
"sourceIdentifier": "[email protected]",
"published": "2026-08-03T16:16:28.387",
"lastModified": "2026-10-30T13:18:33.020",
"vulnStatus": "Modified",
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}
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