{"id":"CVE-2020-8833","aliases":["EUVD-2020-29676","GHSA-w9g5-3qgc-xmgx","UBUNTU-CVE-2020-8833","USN-4315-1","USN-4315-2"],"status":"published","title":"Apport race condition in crash report permissions","description":"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.","severity":{"version":"3.1","score":5.6,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00344,"percentile":0.28257,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-367"],"published":"2020-04-02T00:00:00Z","modified":"2026-06-17T03:27:01Z","fixes":[{"ecosystem":"Ubuntu:Pro:14.04:LTS","package":"apport","fixed_in":["2.14.1-0ubuntu3.29+esm4"],"sources":["osv"]},{"ecosystem":"Ubuntu:16.04:LTS","package":"apport","fixed_in":["2.20.1-0ubuntu2.23"],"sources":["osv"]},{"ecosystem":"Ubuntu:18.04:LTS","package":"apport","fixed_in":["2.20.9-0ubuntu7.14"],"sources":["osv"]},{"ecosystem":"Ubuntu:20.04:LTS","package":"apport","fixed_in":["2.20.11-0ubuntu22"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:Pro:14.04:LTS","package":"apport","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"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"apport","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"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"apport","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"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"apport","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"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"apport","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"],"bundled":2},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"apport","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"],"bundled":2},{"source":"osv","ecosystem":"Ubuntu:Pro:14.04:LTS","package":"apport","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"],"bundled":2}],"products":[{"vendor":"apport_project","product":"apport"},{"vendor":"canonical","product":"apport"},{"vendor":"canonical","product":"ubuntu_linux"}],"references":[{"url":"https://usn.ubuntu.com/4315-1/","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory"]},{"url":"https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1862933","tags":["x_refsource_CONFIRM","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://usn.ubuntu.com/4315-2/","tags":["vendor-advisory","x_refsource_UBUNTU","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-8833"},{"url":"https://github.com/advisories/GHSA-w9g5-3qgc-xmgx"},{"url":"https://ubuntu.com/security/CVE-2020-8833","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-4315-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/notices/USN-4315-2","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-8833","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-8831","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2020-8833","title":"Apport race condition in crash report permissions","description":"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.","status":"published","published":"2020-04-22T21:15:18.859Z","modified":"2024-09-16T20:53:27.66Z","cvss":[{"version":"3.1","score":5.6,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T14:35:50.88562Z"}],"euvd":[{"id":"EUVD-2020-29676","description":"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.","status":"published","published":"2020-04-22T21:15:18Z","modified":"2024-09-16T20:53:27Z","cvss":[{"version":"3.1","score":5.6,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-03T00:55:10.024877Z"}],"ghsa":[{"id":"GHSA-w9g5-3qgc-xmgx","title":"Time-of-check Time-of-use Race Condition vulnerability on crash report ownership change in Apport...","description":"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.","status":"published","published":"2022-05-24T17:16:19Z","modified":"2023-01-29T05:00:49Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T14:44:40.694561Z"}],"nvd":[{"id":"CVE-2020-8833","description":"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.","status":"published","published":"2020-04-22T22:15:12.577Z","modified":"2026-06-17T03:27:01.667Z","cvss":[{"version":"3.1","score":5.6,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":1.9,"vector":"AV:L/AC:M/Au:N/C:P/I:N/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T14:05:59.718774Z"}],"osv":[{"id":"UBUNTU-CVE-2020-8833","description":"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.","status":"published","published":"2020-04-02T00:00:00Z","modified":"2026-02-04T04:25:01.413397Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium"},{"version":"3.1","score":5.6,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:25.728622Z"},{"id":"USN-4315-1","title":"apport vulnerabilities","description":"Maximilien Bourgeteau discovered that the Apport lock file was created with\ninsecure permissions. This could allow a local attacker to escalate their\nprivileges via a symlink attack. (CVE-2020-8831)\n\nMaximilien Bourgeteau discovered a race condition in Apport when setting\ncrash report permissions. This could allow a local attacker to read\narbitrary files via a symlink attack.  (CVE-2020-8833)\n","status":"published","published":"2020-04-02T00:55:53Z","modified":"2026-02-10T04:41:48Z","updated_at":"2026-11-02T16:58:14.547547Z"},{"id":"USN-4315-2","title":"apport vulnerabilities","description":"USN-4315-1 fixed several vulnerabilities in Apport. This update provides\nthe corresponding update for Ubuntu 14.04 ESM.\n\nOriginal advisory details:\n\n Maximilien Bourgeteau discovered that the Apport lock file was created with\n insecure permissions. This could allow a local attacker to escalate their\n privileges via a symlink attack. (CVE-2020-8831)\n\n Maximilien Bourgeteau discovered a race condition in Apport when setting\n crash report permissions. This could allow a local attacker to read\n arbitrary files via a symlink attack.  (CVE-2020-8833)\n","status":"published","published":"2020-06-15T14:51:07Z","modified":"2026-02-10T04:41:48Z","updated_at":"2026-11-02T16:58:14.547547Z"}]}}