{"id":"UBUNTU-CVE-2020-8833","details":"Time-of-check Time-of-use Race Condition vulnerability on crash report ownership change in Apport allows for a possible privilege escalation opportunity. If fs.protected_symlinks is disabled, this can be exploited between the os.open and os.chown calls when the Apport cron script clears out crash files of size 0. A symlink with the same name as the deleted file can then be created upon which chown will be called, changing the file owner to root. Fixed in versions 2.20.1-0ubuntu2.23, 2.20.9-0ubuntu7.14, 2.20.11-0ubuntu8.8 and 2.20.11-0ubuntu22.","modified":"2026-02-04T04:25:01.413397Z","published":"2020-04-02T00:00:00Z","related":["USN-4315-1","USN-4315-2"],"upstream":["CVE-2020-8833"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-8833"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4315-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4315-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2020-8833"}],"affected":[{"package":{"name":"apport","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/apport@2.14.1-0ubuntu3.29+esm4?arch=source&distro=trusty/esm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.14.1-0ubuntu3.29+esm4"}]}],"versions":["2.12.5-0ubuntu2","2.12.6-0ubuntu1","2.12.7-0ubuntu1","2.12.7-0ubuntu2","2.12.7-0ubuntu3","2.12.7-0ubuntu6","2.13.1-0ubuntu1","2.13.1-0ubuntu2","2.13.2-0ubuntu2","2.13.2-0ubuntu3","2.13.2-0ubuntu4","2.13.2-0ubuntu5","2.13.3-0ubuntu1","2.14-0ubuntu1","2.14.1-0ubuntu1","2.14.1-0ubuntu2","2.14.1-0ubuntu3","2.14.1-0ubuntu3.1","2.14.1-0ubuntu3.2","2.14.1-0ubuntu3.3","2.14.1-0ubuntu3.4","2.14.1-0ubuntu3.5","2.14.1-0ubuntu3.6","2.14.1-0ubuntu3.7","2.14.1-0ubuntu3.8","2.14.1-0ubuntu3.9","2.14.1-0ubuntu3.10","2.14.1-0ubuntu3.11","2.14.1-0ubuntu3.12","2.14.1-0ubuntu3.13","2.14.1-0ubuntu3.15","2.14.1-0ubuntu3.16","2.14.1-0ubuntu3.18","2.14.1-0ubuntu3.19","2.14.1-0ubuntu3.20","2.14.1-0ubuntu3.21","2.14.1-0ubuntu3.23","2.14.1-0ubuntu3.24","2.14.1-0ubuntu3.25","2.14.1-0ubuntu3.27","2.14.1-0ubuntu3.28","2.14.1-0ubuntu3.29","2.14.1-0ubuntu3.29+esm1","2.14.1-0ubuntu3.29+esm2","2.14.1-0ubuntu3.29+esm3"],"ecosystem_specific":{"binaries":[{"binary_name":"apport","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"apport-gtk","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"apport-kde","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"apport-noui","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"apport-retrace","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"apport-valgrind","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"dh-apport","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"python-apport","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"python-problem-report","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"python3-apport","binary_version":"2.14.1-0ubuntu3.29+esm4"},{"binary_name":"python3-problem-report","binary_version":"2.14.1-0ubuntu3.29+esm4"}],"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/2020/UBUNTU-CVE-2020-8833.json"}},{"package":{"name":"apport","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/apport@2.20.1-0ubuntu2.23?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.20.1-0ubuntu2.23"}]}],"versions":["2.19.1-0ubuntu3","2.19.2-0ubuntu1","2.19.2-0ubuntu2","2.19.2-0ubuntu3","2.19.2-0ubuntu4","2.19.2-0ubuntu5","2.19.2-0ubuntu6","2.19.2-0ubuntu8","2.19.2-0ubuntu9","2.19.3-0ubuntu1","2.19.3-0ubuntu2","2.19.3-0ubuntu3","2.19.4-0ubuntu1","2.19.4-0ubuntu2","2.20-0ubuntu2","2.20-0ubuntu3","2.20.1-0ubuntu1","2.20.1-0ubuntu2","2.20.1-0ubuntu2.1","2.20.1-0ubuntu2.2","2.20.1-0ubuntu2.4","2.20.1-0ubuntu2.5","2.20.1-0ubuntu2.6","2.20.1-0ubuntu2.9","2.20.1-0ubuntu2.10","2.20.1-0ubuntu2.12","2.20.1-0ubuntu2.13","2.20.1-0ubuntu2.14","2.20.1-0ubuntu2.15","2.20.1-0ubuntu2.16","2.20.1-0ubuntu2.17","2.20.1-0ubuntu2.18","2.20.1-0ubuntu2.19","2.20.1-0ubuntu2.20","2.20.1-0ubuntu2.21","2.20.1-0ubuntu2.22"],"ecosystem_specific":{"binaries":[{"binary_name":"apport","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"apport-gtk","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"apport-kde","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"apport-noui","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"apport-retrace","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"apport-valgrind","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"dh-apport","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"python-apport","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"python-problem-report","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"python3-apport","binary_version":"2.20.1-0ubuntu2.23"},{"binary_name":"python3-problem-report","binary_version":"2.20.1-0ubuntu2.23"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-8833.json"}},{"package":{"name":"apport","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/apport@2.20.9-0ubuntu7.14?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.20.9-0ubuntu7.14"}]}],"versions":["2.20.7-0ubuntu3","2.20.7-0ubuntu3.1","2.20.7-0ubuntu4","2.20.8-0ubuntu1","2.20.8-0ubuntu2","2.20.8-0ubuntu3","2.20.8-0ubuntu4","2.20.8-0ubuntu5","2.20.8-0ubuntu6","2.20.8-0ubuntu7","2.20.8-0ubuntu8","2.20.8-0ubuntu9","2.20.8-0ubuntu10","2.20.9-0ubuntu1","2.20.9-0ubuntu2","2.20.9-0ubuntu4","2.20.9-0ubuntu5","2.20.9-0ubuntu6","2.20.9-0ubuntu7","2.20.9-0ubuntu7.1","2.20.9-0ubuntu7.2","2.20.9-0ubuntu7.3","2.20.9-0ubuntu7.4","2.20.9-0ubuntu7.5","2.20.9-0ubuntu7.6","2.20.9-0ubuntu7.7","2.20.9-0ubuntu7.8","2.20.9-0ubuntu7.9","2.20.9-0ubuntu7.11","2.20.9-0ubuntu7.12","2.20.9-0ubuntu7.13"],"ecosystem_specific":{"binaries":[{"binary_name":"apport","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"apport-gtk","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"apport-kde","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"apport-noui","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"apport-retrace","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"apport-valgrind","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"dh-apport","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"python-apport","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"python-problem-report","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"python3-apport","binary_version":"2.20.9-0ubuntu7.14"},{"binary_name":"python3-problem-report","binary_version":"2.20.9-0ubuntu7.14"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-8833.json"}},{"package":{"name":"apport","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/apport@2.20.11-0ubuntu22?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.20.11-0ubuntu22"}]}],"versions":["2.20.11-0ubuntu8","2.20.11-0ubuntu9","2.20.11-0ubuntu13","2.20.11-0ubuntu14","2.20.11-0ubuntu15","2.20.11-0ubuntu16","2.20.11-0ubuntu17","2.20.11-0ubuntu18","2.20.11-0ubuntu19","2.20.11-0ubuntu20","2.20.11-0ubuntu21"],"ecosystem_specific":{"binaries":[{"binary_name":"apport","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"apport-gtk","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"apport-kde","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"apport-noui","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"apport-retrace","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"apport-valgrind","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"dh-apport","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"python3-apport","binary_version":"2.20.11-0ubuntu22"},{"binary_name":"python3-problem-report","binary_version":"2.20.11-0ubuntu22"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-8833.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]}