{"id":"USN-5174-2","aliases":[],"status":"published","title":"samba regression","description":"USN-5174-1 fixed vulnerabilities in Samba. Some of the changes introduced a\nregression in Kerberos authentication in certain environments.\n\nPlease see the following upstream bug for more information:\nhttps://bugzilla.samba.org/show_bug.cgi?id=14922\n\nThis update fixes the problem.\n\nOriginal advisory details:\n\n Stefan Metzmacher discovered that Samba incorrectly handled SMB1 client\n connections. A remote attacker could possibly use this issue to downgrade\n connections to plaintext authentication. (CVE-2016-2124)\n \n Andrew Bartlett discovered that Samba incorrectly mapping domain users to\n local users. An authenticated attacker could possibly use this issue to\n become root on domain members. (CVE-2020-25717)\n \n Andrew Bartlett discovered that Samba did not properly check sensitive\n attributes. An authenticated attacker could possibly use this issue to\n escalate privileges. (CVE-2020-25722)\n \n Joseph Sutton discovered that Samba incorrectly handled certain TGS\n requests. An authenticated attacker could possibly use this issue to cause\n Samba to crash, resulting in a denial of service. (CVE-2021-3671)\n \n The fix for CVE-2020-25717 results in possible behaviour changes that could\n affect certain environments. Please see the upstream advisory for more\n information:\n \n https://www.samba.org/samba/security/CVE-2020-25717.html","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2021-12-13T19:55:15Z","modified":"2026-04-22T10:19:42Z","fixes":[{"ecosystem":"Ubuntu:18.04:LTS","package":"samba","fixed_in":["2:4.7.6+dfsg~ubuntu-0ubuntu2.27"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"samba","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:4.7.6+dfsg~ubuntu-0ubuntu2.27"}]}],"versions":["2:4.6.7+dfsg-1ubuntu3","2:4.7.1+dfsg-1ubuntu1","2:4.7.3+dfsg-1ubuntu1","2:4.7.4+dfsg-1ubuntu1","2:4.7.6+dfsg~ubuntu-0ubuntu1","2:4.7.6+dfsg~ubuntu-0ubuntu2","2:4.7.6+dfsg~ubuntu-0ubuntu2.2","2:4.7.6+dfsg~ubuntu-0ubuntu2.4","2:4.7.6+dfsg~ubuntu-0ubuntu2.5","2:4.7.6+dfsg~ubuntu-0ubuntu2.6","2:4.7.6+dfsg~ubuntu-0ubuntu2.7","2:4.7.6+dfsg~ubuntu-0ubuntu2.9","2:4.7.6+dfsg~ubuntu-0ubuntu2.10","2:4.7.6+dfsg~ubuntu-0ubuntu2.11","2:4.7.6+dfsg~ubuntu-0ubuntu2.13","2:4.7.6+dfsg~ubuntu-0ubuntu2.14","2:4.7.6+dfsg~ubuntu-0ubuntu2.15","2:4.7.6+dfsg~ubuntu-0ubuntu2.16","2:4.7.6+dfsg~ubuntu-0ubuntu2.17","2:4.7.6+dfsg~ubuntu-0ubuntu2.18","2:4.7.6+dfsg~ubuntu-0ubuntu2.19","2:4.7.6+dfsg~ubuntu-0ubuntu2.20","2:4.7.6+dfsg~ubuntu-0ubuntu2.21","2:4.7.6+dfsg~ubuntu-0ubuntu2.23","2:4.7.6+dfsg~ubuntu-0ubuntu2.24","2:4.7.6+dfsg~ubuntu-0ubuntu2.26"]}],"references":[{"url":"https://ubuntu.com/security/notices/USN-5174-2","tags":["advisory"]},{"url":"https://launchpad.net/bugs/1950363","tags":["report"]}],"sources":{"osv":[{"id":"USN-5174-2","title":"samba regression","description":"USN-5174-1 fixed vulnerabilities in Samba. Some of the changes introduced a\nregression in Kerberos authentication in certain environments.\n\nPlease see the following upstream bug for more information:\nhttps://bugzilla.samba.org/show_bug.cgi?id=14922\n\nThis update fixes the problem.\n\nOriginal advisory details:\n\n Stefan Metzmacher discovered that Samba incorrectly handled SMB1 client\n connections. A remote attacker could possibly use this issue to downgrade\n connections to plaintext authentication. (CVE-2016-2124)\n \n Andrew Bartlett discovered that Samba incorrectly mapping domain users to\n local users. An authenticated attacker could possibly use this issue to\n become root on domain members. (CVE-2020-25717)\n \n Andrew Bartlett discovered that Samba did not properly check sensitive\n attributes. An authenticated attacker could possibly use this issue to\n escalate privileges. (CVE-2020-25722)\n \n Joseph Sutton discovered that Samba incorrectly handled certain TGS\n requests. An authenticated attacker could possibly use this issue to cause\n Samba to crash, resulting in a denial of service. (CVE-2021-3671)\n \n The fix for CVE-2020-25717 results in possible behaviour changes that could\n affect certain environments. Please see the upstream advisory for more\n information:\n \n https://www.samba.org/samba/security/CVE-2020-25717.html\n","status":"published","published":"2021-12-13T19:55:15Z","modified":"2026-04-22T10:19:42.455809Z","updated_at":"2026-11-02T16:58:15.683829Z"}]}}