{"id":"UBUNTU-CVE-2021-23240","details":"selinux_edit_copy_tfiles in sudoedit in Sudo before 1.9.5 allows a local unprivileged user to gain file ownership and escalate privileges by replacing a temporary file with a symlink to an arbitrary file target. This affects SELinux RBAC support in permissive mode. Machines without SELinux are not vulnerable.","modified":"2025-09-08T16:46:59Z","published":"2021-01-12T09:15:00Z","upstream":["CVE-2021-23240"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-23240"},{"type":"REPORT","url":"https://www.openwall.com/lists/oss-security/2021/01/11/2"},{"type":"REPORT","url":"https://www.sudo.ws/alerts/sudoedit_selinux.html"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-23240"}],"affected":[{"package":{"name":"sudo","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.9p5-1ubuntu1.5+esm8?arch=source&distro=esm-infra-legacy/trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"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","1.8.9p5-1ubuntu1.5+esm3","1.8.9p5-1ubuntu1.5+esm5","1.8.9p5-1ubuntu1.5+esm6","1.8.9p5-1ubuntu1.5+esm7","1.8.9p5-1ubuntu1.5+esm8"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.9p5-1ubuntu1.5+esm8"},{"binary_name":"sudo-ldap","binary_version":"1.8.9p5-1ubuntu1.5+esm8"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-23240.json"}},{"package":{"name":"sudo","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.16-0ubuntu1.10+esm3?arch=source&distro=esm-infra/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"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","1.8.16-0ubuntu1.9","1.8.16-0ubuntu1.10","1.8.16-0ubuntu1.10+esm1","1.8.16-0ubuntu1.10+esm2","1.8.16-0ubuntu1.10+esm3"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.16-0ubuntu1.10+esm3"},{"binary_name":"sudo-ldap","binary_version":"1.8.16-0ubuntu1.10+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-23240.json"}},{"package":{"name":"sudo","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.21p2-3ubuntu1.6+esm1?arch=source&distro=esm-infra/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.20p2-1ubuntu1","1.8.21p2-2ubuntu1","1.8.21p2-3ubuntu1","1.8.21p2-3ubuntu1.1","1.8.21p2-3ubuntu1.2","1.8.21p2-3ubuntu1.3","1.8.21p2-3ubuntu1.4","1.8.21p2-3ubuntu1.5","1.8.21p2-3ubuntu1.6","1.8.21p2-3ubuntu1.6+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.21p2-3ubuntu1.6+esm1"},{"binary_name":"sudo-ldap","binary_version":"1.8.21p2-3ubuntu1.6+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-23240.json"}},{"package":{"name":"sudo","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/sudo@1.8.31-1ubuntu1.5+esm1?arch=source&distro=esm-infra/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.27-1ubuntu4","1.8.29-1ubuntu1","1.8.31-1ubuntu1","1.8.31-1ubuntu1.1","1.8.31-1ubuntu1.2","1.8.31-1ubuntu1.4","1.8.31-1ubuntu1.5","1.8.31-1ubuntu1.5+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"sudo","binary_version":"1.8.31-1ubuntu1.5+esm1"},{"binary_name":"sudo-ldap","binary_version":"1.8.31-1ubuntu1.5+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-23240.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":"negligible"}]}