{"id":"USN-5142-3","aliases":[],"status":"published","title":"samba regression","description":"USN-5142-1 fixed vulnerabilities in Samba. Some of the upstream changes\nintroduced a regression 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 correctly sandbox Kerberos\n tickets issues by an RODC. An RODC could print administrator tickets,\n contrary to expectations. (CVE-2020-25718)\n \n Andrew Bartlett discovered that Samba incorrectly handled Kerberos tickets.\n Delegated administrators could possibly use this issue to impersonate\n accounts, leading to total domain compromise. (CVE-2020-25719)\n \n Andrew Bartlett discovered that Samba did not provide stable AD\n identifiers to Kerberos acceptors. (CVE-2020-25721)\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 Stefan Metzmacher discovered that Samba incorrectly handled certain large\n DCE/RPC requests. A remote attacker could possibly use this issue to\n bypass signature requirements. (CVE-2021-23192)\n \n William Ross discovered that Samba incorrectly handled memory. A remote\n attacker could use this issue to cause Samba to crash, resulting in a\n denial of service, or possibly escalate privileges. (CVE-2021-3738)\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":"2021-12-13T19:47:42Z","modified":"2026-04-22T10:18:26Z","fixes":[{"ecosystem":"Ubuntu:20.04:LTS","package":"samba","fixed_in":["2:4.13.14+dfsg-0ubuntu0.20.04.4"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"samba","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:4.13.14+dfsg-0ubuntu0.20.04.4"}]}],"versions":["2:4.10.7+dfsg-0ubuntu2","2:4.10.7+dfsg-0ubuntu3","2:4.11.1+dfsg-3ubuntu1","2:4.11.1+dfsg-3ubuntu2","2:4.11.1+dfsg-3ubuntu4","2:4.11.5+dfsg-1ubuntu1","2:4.11.5+dfsg-1ubuntu2","2:4.11.6+dfsg-0ubuntu1","2:4.11.6+dfsg-0ubuntu1.1","2:4.11.6+dfsg-0ubuntu1.2","2:4.11.6+dfsg-0ubuntu1.3","2:4.11.6+dfsg-0ubuntu1.4","2:4.11.6+dfsg-0ubuntu1.5","2:4.11.6+dfsg-0ubuntu1.6","2:4.11.6+dfsg-0ubuntu1.8","2:4.11.6+dfsg-0ubuntu1.9","2:4.11.6+dfsg-0ubuntu1.10","2:4.13.14+dfsg-0ubuntu0.20.04.1","2:4.13.14+dfsg-0ubuntu0.20.04.2","2:4.13.14+dfsg-0ubuntu0.20.04.3"]}],"references":[{"url":"https://ubuntu.com/security/notices/USN-5142-3","tags":["advisory"]},{"url":"https://launchpad.net/bugs/1950363","tags":["report"]}],"sources":{"osv":[{"id":"USN-5142-3","title":"samba regression","description":"USN-5142-1 fixed vulnerabilities in Samba. Some of the upstream changes\nintroduced a regression 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 correctly sandbox Kerberos\n tickets issues by an RODC. An RODC could print administrator tickets,\n contrary to expectations. (CVE-2020-25718)\n \n Andrew Bartlett discovered that Samba incorrectly handled Kerberos tickets.\n Delegated administrators could possibly use this issue to impersonate\n accounts, leading to total domain compromise. (CVE-2020-25719)\n \n Andrew Bartlett discovered that Samba did not provide stable AD\n identifiers to Kerberos acceptors. (CVE-2020-25721)\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 Stefan Metzmacher discovered that Samba incorrectly handled certain large\n DCE/RPC requests. A remote attacker could possibly use this issue to\n bypass signature requirements. (CVE-2021-23192)\n \n William Ross discovered that Samba incorrectly handled memory. A remote\n attacker could use this issue to cause Samba to crash, resulting in a\n denial of service, or possibly escalate privileges. (CVE-2021-3738)\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":"2021-12-13T19:47:42Z","modified":"2026-04-22T10:18:26.431825Z","updated_at":"2026-11-02T16:58:15.683829Z"}]}}