CVE-2026-29111 systemd: Local unprivileged user can trigger an assert

What is CVE-2026-29111?

CVE-2026-29111 is a medium-severity denial of service vulnerability in Systemd Project Systemd, published on 23 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

systemd, a system and service manager, (as PID 1) hits an assert and freezes execution when an unprivileged IPC API call is made with spurious data. On version v249 and older the effect is not an assert, but stack overwriting, with the attacker controlled content. From version v250 and newer this is not possible as the safety check causes an assert instead. This IPC call was added in v239, so versions older than that are not affected. Versions 260-rc1, 259.2, 258.5, and 257.11 contain patches. No known workarounds are available.

Weakness: CWE-269

Which versions are affected by CVE-2026-29111?

It affects 1 product.

Products include Systemd Project Systemd.

How do I fix CVE-2026-29111?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-29111 being exploited?

There is no known exploitation of CVE-2026-29111 in the wild and no public exploit code.

Other vulnerabilities in Systemd Project Systemd

• CVE-2015-7510 Memory corruption in n/a Critical 9.8
• CVE-2017-1000082 Privilege escalation in n/a Critical 9.8
• CVE-2016-10156 Privilege escalation in n/a High 7.8
• CVE-2017-9445 Memory corruption in n/a High 7.5
• CVE-2017-9217 Null dereference in n/a High 7.5

All Systemd Project Systemd vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALSA-2026:13651, ALSA-2026:13677, ALSA-2026:19068, ALSA-2026:19213, AZL-80538, AZL-80937 and 26 more.