CVE-2026-29111
Stack Overflow in systemd IPC Causes PID 1 Crash or Freeze
Publication date: 2026-03-23
Last updated on: 2026-04-15
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| systemd_project | systemd | From 239 (inc) to 257.11 (exc) |
| systemd_project | systemd | From 258 (inc) to 258.5 (exc) |
| systemd_project | systemd | From 259 (inc) to 259.2 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-269 | The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability affects systemd, a system and service manager running as PID 1. When an unprivileged IPC API call is made with spurious (malformed or unexpected) data, systemd either hits an assert and freezes execution or, in older versions, experiences stack overwriting with attacker-controlled content.
Specifically, in versions up to v249, the vulnerability allows stack overwriting, which means an attacker can overwrite parts of the systemd process stack with their own data. From version v250 onwards, a safety check causes an assert failure instead, which freezes systemd but prevents stack corruption.
This IPC call was introduced in version v239, so versions older than that are not affected. Several patched versions (260-rc1, 259.2, 258.5, and 257.11) have addressed this issue. No known workarounds are available.
How can this vulnerability impact me? :
The vulnerability can cause systemd, the core system and service manager, to freeze or have its stack overwritten by attacker-controlled data. This can lead to a denial of service (DoS) condition where the system becomes unresponsive.
Because systemd runs as PID 1, its failure can halt or severely disrupt the entire system's operation, potentially requiring a reboot or manual intervention.
The CVSS score of 5.5 indicates a medium severity impact, with the main impact being availability (A:H), meaning the system's availability is highly affected.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should update systemd to a patched version. Versions 260-rc1, 259.2, 258.5, and 257.11 contain patches that address this issue.
No known workarounds are available, so applying the update is the immediate recommended action.