Vulnerability identifier: #VU55034

Vulnerability risk: Low

CVSSv3.1: 5 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-33910

CWE-ID: CWE-789

Exploitation vector: Local

Exploit availability: Yes

Vulnerable software:
systemd
Server applications / Other server solutions

Vendor: Freedesktop.org

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to stack exhaustion within the basic/unit-name.c in systemd. A local user can crash the systemd (PID 1) and cause a kernel panic.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

systemd: 220 - 249

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External links
http://www.openwall.com/lists/oss-security/2021/07/20/2
http://github.com/systemd/systemd/pull/20256/commits/441e0115646d54f080e5c3bb0ba477c892861ab9

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.