PT-2020-5173 · Canonical · Apport+1

Maximilien Bourgeteau · Published 2020-04-02 · Updated 2022-10-07 · CVE-2020-8831

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N

Name of the Vulnerable Software and Affected Versions Apport versions prior to 2.20.1-0ubuntu2.23 Apport versions prior to 2.20.9-0ubuntu7.14 Apport versions prior to 2.20.11-0ubuntu8.8 Apport versions prior to 2.20.11-0ubuntu22

Description The issue is related to Apport creating a world-writable lock file with root ownership in the /var/lock/apport directory. If the apport directory does not exist, it will be created. This allows for a symlink attack if an attacker creates a symlink at /var/lock/apport, changing Apport's lock file location. The file could then be used to escalate privileges.

Recommendations For versions prior to 2.20.1-0ubuntu2.23, update to version 2.20.1-0ubuntu2.23 or later. For versions prior to 2.20.9-0ubuntu7.14, update to version 2.20.9-0ubuntu7.14 or later. For versions prior to 2.20.11-0ubuntu8.8, update to version 2.20.11-0ubuntu8.8 or later. For versions prior to 2.20.11-0ubuntu22, update to version 2.20.11-0ubuntu22 or later. As a temporary workaround, consider restricting access to the /var/lock/apport directory to minimize the risk of exploitation.

Exploit

Fix

Link Following

Weakness Enumeration

CWE-379

CWE-59

Related Identifiers

BDU:2020-05786

CVE-2020-8831

USN-4315-1

USN-4315-2

Affected Products

Apport

Ubuntu

References · 15

• 🔥 https://launchpad.net/bugs/1862348 · Exploit
• https://ubuntu.com/security/CVE-2020-8831 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-4315-2 · Vendor Advisory
• https://osv.dev/vulnerability/USN-4315-1 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-4315-1 · Vendor Advisory
• https://osv.dev/vulnerability/USN-4315-2 · Vendor Advisory
• https://usn.ubuntu.com/4315-2 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2020-8831 · Vendor Advisory
• https://ubuntu.com/security/CVE-2020-8833 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2020-8831 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2020-8831 · Security Note
• https://cve.org/CVERecord?id=CVE-2020-8831 · Security Note
• https://bdu.fstec.ru/vul/2020-05786 · Security Note
• https://people.canonical.com/~ubuntu-security/cve/2020/CVE-2020-8831.html?_ga=2.74318807.450416423.1585882474-997510329.1585215282 · Note
• https://usn.ubuntu.com/4315-1 · Note