{"id":"CVE-2018-20835","aliases":["CLSA-2026-1774484497","EUVD-2019-0483","GHSA-x2mc-8fgj-3wmr","fix-test-env-compat"],"status":"published","title":"Improper Input Validation in tar-fs","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","severity":{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-08","score":0.02359,"percentile":0.83871,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20"],"published":"2019-04-30T18:02:13Z","modified":"2026-10-20T10:48:04Z","fixes":[{"ecosystem":"npm","package":"tar-fs","fixed_in":["1.16.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"tar-fs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.16.2"}]}]},{"source":"osv","ecosystem":"TuxCare:npm","package":"tar-fs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.5.1-tuxcare.0"},{"fixed":"1.5.1-tuxcare.1"}]}],"versions":["1.5.1"],"bundled":4},{"source":"osv","ecosystem":"npm","package":"tar-fs","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.16.2"}]}]}],"products":[{"vendor":"tar-fs_project","product":"tar-fs"}],"references":[{"url":"https://hackerone.com/reports/344595","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","evidence","web"]},{"url":"https://github.com/mafintosh/tar-fs/commit/06672828e6fa29ac8551b1b6f36c852a9a3c58a2","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/mafintosh/tar-fs/compare/d590fc7...a35ce2f","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-20835","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-x2mc-8fgj-3wmr"}],"sources":{"cve":[{"id":"CVE-2018-20835","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","status":"published","published":"2019-04-30T18:02:13Z","modified":"2024-08-05T12:12:26.89Z","updated_at":"2026-11-02T14:34:59.872731Z"}],"euvd":[{"id":"EUVD-2019-0483","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","status":"published","published":"2019-04-30T18:02:13Z","modified":"2024-08-05T12:12:26Z","updated_at":"2026-11-03T02:39:29.769885Z"}],"ghsa":[{"id":"GHSA-x2mc-8fgj-3wmr","title":"Improper Input Validation in tar-fs","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","status":"published","published":"2019-05-01T18:37:18Z","modified":"2023-02-01T05:01:40Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:36:30.61364Z"}],"nvd":[{"id":"CVE-2018-20835","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","status":"published","published":"2019-04-30T19:29:03.437Z","modified":"2026-06-17T01:53:33.67Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":6.4,"vector":"AV:N/AC:L/Au:N/C:N/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:04:57.307075Z"}],"osv":[{"id":"CVE-2018-20835","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","status":"published","published":"2019-04-30T19:29:03.437Z","modified":"2026-10-20T10:48:04.153637004Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:09.145458Z"},{"id":"GHSA-x2mc-8fgj-3wmr","title":"Improper Input Validation in tar-fs","description":"A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.","status":"published","published":"2019-05-01T18:37:18Z","modified":"2023-11-08T04:00:12.89253Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:46:59.484835Z"},{"id":"CLSA-2026-1774484497","title":"TuxCare security update for tar-fs (5 CVEs)","description":"TuxCare rebuilt tar-fs to address 5 CVEs. Fixed in 1.5.1-tuxcare.1.","status":"published","published":"2026-08-04T14:52:15Z","modified":"2026-10-15T09:47:03.625091925Z","updated_at":"2026-11-02T15:43:43.621843Z"}]}}