{"id":"DEBIAN-CVE-2026-18508","details":"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.","modified":"2026-09-23T09:00:13.220992071Z","published":"2026-08-03T16:16:28.387Z","upstream":["CVE-2026-18508"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-18508"}],"affected":[{"package":{"name":"tar","ecosystem":"Debian:12","purl":"pkg:deb/debian/tar?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.34+dfsg-1.2","1.34+dfsg-1.2+deb12u1","1.34+dfsg-1.3","1.34+dfsg-1.4","1.35+dfsg-1","1.35+dfsg-2","1.35+dfsg-3","1.35+dfsg-3.1","1.35+dfsg-4","1.35+dfsg-5","1.35+dfsg-5+hurd.1","1.35+dfsg-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-18508.json"}},{"package":{"name":"tar","ecosystem":"Debian:13","purl":"pkg:deb/debian/tar?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.35+dfsg-3.1","1.35+dfsg-4","1.35+dfsg-5","1.35+dfsg-5+hurd.1","1.35+dfsg-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-18508.json"}},{"package":{"name":"tar","ecosystem":"Debian:14","purl":"pkg:deb/debian/tar?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.35+dfsg-3.1","1.35+dfsg-4","1.35+dfsg-5","1.35+dfsg-5+hurd.1","1.35+dfsg-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-18508.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"}]}