FKIE_CVE-2020-8833

Vulnerability from fkie_nvd - Published: 2020-04-22 22:15 - Updated: 2024-11-21 05:39
Severity ?
5.6 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Summary
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.
References
security@ubuntu.comhttps://bugs.launchpad.net/ubuntu/+source/apport/+bug/1862933Exploit, Third Party Advisory
security@ubuntu.comhttps://usn.ubuntu.com/4315-1/Third Party Advisory
security@ubuntu.comhttps://usn.ubuntu.com/4315-2/Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1862933Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://usn.ubuntu.com/4315-1/Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://usn.ubuntu.com/4315-2/Third Party Advisory
Impacted products
Vendor Product Version
canonical ubuntu_linux 14.04
canonical ubuntu_linux 16.04
canonical ubuntu_linux 18.04
canonical ubuntu_linux 19.10
apport_project apport -
To clipboard 

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