CVE-2020-8831
Fixed in a distro release EPSS <1%CVSS 6.5
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.
Products: Canonical apport
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu 16.04 LTS | apport | 2.20.1-0ubuntu2.23 |
| Ubuntu 18.04 LTS | apport | 2.20.9-0ubuntu7.14 |
| Ubuntu 20.04 LTS | apport | 2.20.11-0ubuntu22 |
| Ubuntu Pro 14.04 LTS | apport | 2.14.1-0ubuntu3.29+esm4 |