{"id":"UBUNTU-CVE-2019-18634","details":"In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.","modified":"2026-02-04T02:30:00.544336Z","published":"2020-01-31T00:00:00Z","related":["USN-4263-1","USN-4263-2"],"upstream":["CVE-2019-18634"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2019-18634"},{"type":"REPORT","url":"https://www.openwall.com/lists/oss-security/2020/01/30/6"},{"type":"REPORT","url":"https://www.openwall.com/lists/oss-security/2020/01/31/1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4263-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4263-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2019-18634"}],"affected":[{"package":{"name":"sudo","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.9p5-1ubuntu1.5+esm3?arch=source&distro=trusty/esm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.9p5-1ubuntu1.5+esm3"}]}],"versions":["1.8.6p3-0ubuntu3","1.8.8-2ubuntu1","1.8.8-2ubuntu2","1.8.9p4-1ubuntu1","1.8.9p4-1ubuntu2","1.8.9p5-1ubuntu1","1.8.9p5-1ubuntu1.1","1.8.9p5-1ubuntu1.2","1.8.9p5-1ubuntu1.3","1.8.9p5-1ubuntu1.4","1.8.9p5-1ubuntu1.5+esm1","1.8.9p5-1ubuntu1.5+esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.9p5-1ubuntu1.5+esm3"},{"binary_name":"sudo-ldap","binary_version":"1.8.9p5-1ubuntu1.5+esm3"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-18634.json"}},{"package":{"name":"sudo","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.16-0ubuntu1.9?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.16-0ubuntu1.9"}]}],"versions":["1.8.12-1ubuntu3","1.8.16-0ubuntu1","1.8.16-0ubuntu1.1","1.8.16-0ubuntu1.2","1.8.16-0ubuntu1.3","1.8.16-0ubuntu1.4","1.8.16-0ubuntu1.5","1.8.16-0ubuntu1.6","1.8.16-0ubuntu1.7","1.8.16-0ubuntu1.8"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.16-0ubuntu1.9"},{"binary_name":"sudo-ldap","binary_version":"1.8.16-0ubuntu1.9"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-18634.json"}},{"package":{"name":"sudo","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.21p2-3ubuntu1.2?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.21p2-3ubuntu1.2"}]}],"versions":["1.8.20p2-1ubuntu1","1.8.21p2-2ubuntu1","1.8.21p2-3ubuntu1","1.8.21p2-3ubuntu1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.21p2-3ubuntu1.2"},{"binary_name":"sudo-ldap","binary_version":"1.8.21p2-3ubuntu1.2"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-18634.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"low"}]}