#VU69807 Off-by-one in systemd - CVE-2022-3821

Vulnerability identifier: #VU69807

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2022-3821

CWE-ID: CWE-193

Exploitation vector: Local

Exploit availability: No

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 an off-by-one error within the format_timespan() function in time-util.c. A local user can trigger an off-by-one error and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

systemd: 250 - 251.7

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External links
https://github.com/systemd/systemd/issues/23928
https://github.com/systemd/systemd/commit/9102c625a673a3246d7e73d8737f3494446bad4e
https://github.com/systemd/systemd/pull/23933
https://bugzilla.redhat.com/show_bug.cgi?id=2139327
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RVBQC2VLSDVQAPJTEMTREXDL4HYLXG2P/

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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.