CVE-2021-3899

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-06-03 · updated 2026-06-17
Weakness: CWE-367

Description

There is a race condition in the 'replaced executable' detection that, with the correct local configuration, allow an attacker to execute arbitrary code as root.

Affected products

Canonical apport: before 2.21.0 — fixed in 2.21.0
Canonical Ubuntu Linux: 18.04, 20.04, 21.10, 22.04

How to fix

Upgrade to a fixed version: Canonical apport 2.21.0. Check the vendor advisory for mitigations.

References

https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1948376
https://ubuntu.com/security/notices/USN-5427-1
https://www.cve.org/CVERecord?id=CVE-2021-3899
https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1948376
https://ubuntu.com/security/notices/USN-5427-1
https://www.cve.org/CVERecord?id=CVE-2021-3899

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