CVE-2020-8831 - CVE House
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Status published Medium CVE-2020-8831

World writable root owned lock file created in user controllable location

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Maximilien Bourgeteau

References

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Affected Vendor

Affected Software

Apport
Vulnerable Versions:
2.20.1, 2.20.9, 2.20.11

Timeline

Official Publish: April 22nd, 2020
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N

Weaknesses (CWE)

CWE-379

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.