Abitrary file write through systemd-creds option_CVE-2026-33945

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CRITICAL

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

Description

Incus is a system container and virtual machine manager. Incus instances have an option to provide credentials to systemd in the guest. For containers, this is handled through a shared directory. Prior to version 6.23.0, an attacker can set a configuration key named something like `systemd.credential.../../../../../../root/.bashrc` to cause Incus to write outside of the `credentials` directory associated with the container. This makes use of the fact that the Incus syntax for such credentials is `systemd.credential.XYZ` where `XYZ` can itself contain more periods. While it's not possible to read any data this way, it's possible to write to arbitrary files as root, enabling both privilege escalation and denial of service attacks. Version 6.23.0 fixes the issue.

Basic Information

ID CVE-2026-33945

Source GitHub_M

Published Mar 26, 2026 at 23:27

Modified Mar 27, 2026 at 20:00

Affected Product

Vendor lxc

Product incus

Version < 6.23.0

Affected Versions lxc incus < 6.23.0

CWE Classification

CWE-22

References

github.com /lxc/incus/security/advisories/GHSA-q4q8-7f2j-9h9f

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    "published": "2026-03-26T23:27:45.711Z",
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