{"id":"CVE-2018-20482","title":"GNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed …","summary":"GNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed …","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-835"],"vendor":"gnu","product":"tar","affected":["tar <= 1.30","debian_linux = 8.0","debian_linux = 9.0","leap = 15.0"],"published":"2018-12-26","updated":"2026-10-14","sourceUpdated":"2026-10-14T07:16:43.667","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2018-20482","references":[{"url":"http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454","label":"cve@mitre.org"},{"url":"http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.html","label":"cve@mitre.org"},{"url":"http://www.securityfocus.com/bid/106354","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2018/12/msg00023.html","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2021/11/msg00025.html","label":"cve@mitre.org"},{"url":"https://news.ycombinator.com/item?id=18745431","label":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/201903-05","label":"cve@mitre.org"},{"url":"https://twitter.com/thatcks/status/1076166645708668928","label":"cve@mitre.org"},{"url":"https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBug","label":"cve@mitre.org"},{"url":"http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/106354","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2018/12/msg00023.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2021/11/msg00025.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://news.ycombinator.com/item?id=18745431","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201903-05","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://twitter.com/thatcks/status/1076166645708668928","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBug","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2018/cve-2018-20482.json"},{"url":"https://access.redhat.com/security/cve/CVE-2018-20482"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1662346"},{"url":"https://www.cve.org/CVERecord?id=CVE-2018-20482"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-20482"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.0053,"epssPercentile":0.4329,"ingestedAt":"2026-10-14T07:21:04.803Z","scores":{"nvd":4.7,"vendor":5.5},"slug":"CVE-2018-20482","body":"## Overview\n\nGNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed to be archived by a different user's process (e.g., a system backup running as root).\n\n## Affected\n\n- `tar <= 1.30`\n- `debian_linux = 8.0`\n- `debian_linux = 9.0`\n- `leap = 15.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 5, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 · no fix planned: Red Hat Enterprise Linux 5, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 · updated 2026-10-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2018/cve-2018-20482.json)","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":25.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}