Vulnerability · Published Apr 22, 2020 · Assigned by canonical

CVE-2020-8831World writable root owned lock file created in user controllable location

Medium 6.5

In plain English

A medium-severity security flaw in Apport from Canonical. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 51% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.7%top 48.6% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
Canonical	Apport	2.20.1 – before 2.20.1-0ubuntu2.232.20.9 – before 2.20.9-0ubuntu7.142.20.11 – before 2.20.11-0ubuntu8.8

Weakness: CWE-379 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N

References

https://launchpad.net/bugs/1862348 x_refsource_CONFIRM
https://usn.ubuntu.com/4315-1/ x_refsource_CONFIRM
USN-4315-2 vendor-advisory, x_refsource_UBUNTU