CVE-2020-8831
If the apport/ directory does not exist (this is not uncommon as /var/lock is a tmpfs), it will create the directory, otherwise it will simply continue execution using the existing directory.
Does this matter?
Lower severity and a low EPSS score (0.65%). Track it; it rarely justifies an emergency change on its own.
Description
Apport creates a world writable lock file with root ownership in the world writable /var/lock/apport directory. If the apport/ directory does not exist (this is not uncommon as /var/lock is a tmpfs), it will create the directory, otherwise it will simply continue execution using the existing directory. This allows for a symlink attack if an attacker were to create a symlink at /var/lock/apport, changing apport's lock file location. This file could then be used to escalate privileges, for example. Fixed in versions 2.20.1-0ubuntu2.23, 2.20.9-0ubuntu7.14, 2.20.11-0ubuntu8.8 and 2.20.11-0ubuntu22.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 0.65% probability · 49th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-379, CWE-59
- Affected
- canonical/ubuntu linux · apport project/apport
- Source
- security@ubuntu.com
References
- https://launchpad.net/bugs/1862348Exploit, Third Party Advisory
- https://usn.ubuntu.com/4315-1/Third Party Advisory
- https://usn.ubuntu.com/4315-2/Third Party Advisory
- https://launchpad.net/bugs/1862348Exploit, Third Party Advisory
- https://usn.ubuntu.com/4315-1/Third Party Advisory
- https://usn.ubuntu.com/4315-2/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.