CVE-2021-3899

HIGH

Published Jun 3, 2024 Modified Aug 26, 2025 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.

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CVSS v3.1 Score

7.8

HIGH

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

Weakness Type (CWE)

CWE-367 CWE-367

Affected Products

Vendor	Product	Versions
canonical	apport	< 2.21.0
canonical	ubuntu_linux	All
canonical	ubuntu_linux	All
canonical	ubuntu_linux	All
canonical	ubuntu_linux	All

References

Advisories & Patches

https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1948376 https://ubuntu.com/security/notices/USN-5427-1 https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1948376 https://ubuntu.com/security/notices/USN-5427-1

Other References

https://www.cve.org/CVERecord?id=CVE-2021-3899 https://www.cve.org/CVERecord?id=CVE-2021-3899

Frequently Asked Questions

What is CVE-2021-3899? +

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. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2021-3899? +

CVE-2021-3899 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2021-3899? +

CVE-2021-3899 affects products from canonical, specifically: apport, ubuntu_linux. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-3899? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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