{"id":"CVE-2021-38173","aliases":["DEBIAN-CVE-2021-38173","DLA-2755-1","EUVD-2021-24643","GHSA-c38g-xjq6-3v46","UBUNTU-CVE-2021-38173","USN-9049-1"],"status":"published","title":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering...","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.03155,"percentile":0.88142,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-77"],"published":"2021-08-07T18:58:19Z","modified":"2026-11-12T17:29:22Z","fixes":[{"ecosystem":"Debian:12","package":"btrbk","fixed_in":["0.27.1-2"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"btrbk","fixed_in":["0.27.1-2"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"btrbk","fixed_in":["0.27.1-2"],"sources":["osv"]},{"ecosystem":"Debian:9","package":"btrbk","fixed_in":["0.24.0-1+deb9u1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"btrbk","fixed_in":["0.26.0-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:20.04:LTS","package":"btrbk","fixed_in":["0.27.1-1ubuntu0.1~esm1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.27.1-2"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.27.1-2"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.27.1-2"}]}]},{"source":"osv","ecosystem":"Debian:9","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.24.0-1+deb9u1"}]}],"versions":["0.24.0-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.26.0-1ubuntu0.1~esm1"}]}],"versions":["0.25.1-1","0.26.0-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.27.1-1ubuntu0.1~esm1"}]}],"versions":["0.27.1-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.26.0-1ubuntu0.1~esm1"}]}],"versions":["0.25.1-1","0.26.0-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"btrbk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.27.1-1ubuntu0.1~esm1"}]}],"versions":["0.27.1-1"]}],"products":[{"vendor":"debian","product":"debian_linux"},{"vendor":"digint","product":"btrbk"},{"vendor":"fedoraproject","product":"fedora"}],"references":[{"url":"https://github.com/digint/btrbk/commit/58212de771c381cd4fa05625927080bf264e9584","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","report"]},{"url":"https://github.com/digint/btrbk/blob/master/ChangeLog","tags":["x_refsource_CONFIRM","x_transferred","Release Notes","Third Party Advisory","advisory","report"]},{"url":"https://lists.debian.org/debian-lts-announce/2021/09/msg00002.html","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LM7GLTUN5YS4KE2RNBX732EAMVVGNEX3/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BP2T32JMENJFRP2HWXR7FTTZVRTTPECL/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-38173"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BP2T32JMENJFRP2HWXR7FTTZVRTTPECL/"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LM7GLTUN5YS4KE2RNBX732EAMVVGNEX3/"},{"url":"https://github.com/advisories/GHSA-c38g-xjq6-3v46"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-38173","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-38173","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-38173","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-9049-1","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2021-38173","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2021-08-07T18:58:19Z","modified":"2024-08-04T01:37:15.793Z","updated_at":"2026-11-02T14:33:07.697752Z"}],"euvd":[{"id":"EUVD-2021-24643","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2021-08-07T18:58:19Z","modified":"2024-08-04T01:37:15Z","updated_at":"2026-11-03T03:24:25.678078Z"}],"ghsa":[{"id":"GHSA-c38g-xjq6-3v46","title":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering...","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2022-05-24T19:10:20Z","modified":"2023-01-30T05:01:18Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-77"],"updated_at":"2026-11-02T14:46:22.963176Z"}],"nvd":[{"id":"CVE-2021-38173","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2021-08-07T19:15:06.997Z","modified":"2026-06-17T04:01:41.707Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-77"],"updated_at":"2026-11-02T14:06:56.562207Z"}],"osv":[{"id":"CVE-2021-38173","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2021-08-07T19:15:06.997Z","modified":"2026-10-20T10:54:51.554748055Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:44:20.843843Z"},{"id":"DEBIAN-CVE-2021-38173","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2021-08-07T19:15:06.997Z","modified":"2026-10-23T18:05:23.43920938Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:45:35.521549Z"},{"id":"UBUNTU-CVE-2021-38173","description":"Btrbk before 0.31.2 allows command execution because of the mishandling of remote hosts filtering SSH commands using ssh_filter_btrbk.sh in authorized_keys.","status":"published","published":"2021-08-07T19:15:00Z","modified":"2026-11-12T17:22:48.592744598Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-12T18:02:32.471989Z"},{"id":"DLA-2755-1","title":"btrbk - security update","status":"published","published":"2021-09-05T00:00:00Z","modified":"2026-03-09T01:19:01.231331Z","updated_at":"2026-11-02T15:46:11.189256Z"},{"id":"USN-9049-1","title":"btrbk vulnerability","description":"It was discovered that btrbk incorrectly filtered SSH commands received\nfrom remote hosts. A remote attacker could possibly use this issue to\nexecute arbitrary commands.","status":"published","published":"2026-11-11T18:31:40Z","modified":"2026-11-12T17:29:22.948016463Z","updated_at":"2026-11-12T18:08:46.665847Z"}]}}