CVE-2026-23954 Incus container image templating arbitrary host file read and write
Attackers with container launch privileges can exploit path traversal in image templating to read/write host files and execute arbitrary commands.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-23954?
CVE-2026-23954 is a high-severity path traversal vulnerability in lxc incus, published on 22 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Incus is a system container and virtual machine manager. Versions 6.21.0 and below allow a user with the ability to launch a container with a custom image (e.g a member of the ‘incus’ group) to use directory traversal or symbolic links in the templating functionality to achieve host arbitrary file read, and host arbitrary file write. This ultimately results in arbitrary command execution on the host. When using an image with a metadata.yaml containing templates, both the source and target paths are not checked for symbolic links or directory traversal. This can also be exploited in IncusOS. A fix is planned for versions 6.0.6 and 6.21.0, but they have not been released at the time of publication.
Weakness: CWE-22
Which versions are affected by CVE-2026-23954?
4 open source packages ship an affected version, including github.com/lxc/incus/v6/cmd/incusd, github.com/lxc/incus and github.com/lxc/incus/v6. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/lxc/incus/v6/cmd/incusd Go | All versions | None |
github.com/lxc/incus/v6/cmd/incusd Go | All versions | None |
github.com/lxc/incus Go | All versions | None |
github.com/lxc/incus/v6 Go | From 6.1.0 | None |
Products include Linuxcontainers Incus.
How do I fix CVE-2026-23954?
Upgrade to a fixed version.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-23954 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-23954 exists.
Other vulnerabilities in lxc incus
- CVE-2026-33897 Incus vulnerable to arbitrary file read and write through pongo templates
- CVE-2026-33945 Abitrary file write through systemd-creds option
- CVE-2026-33898 Local Incus UI web server vulnerable to nuthentication bypass
- CVE-2026-23953 Incus container environment configuration newline injection
- CVE-2025-64507 Incus vulnerable to local privilege escalation through custom storage volumes
Sources
Also known as DEBIAN-CVE-2026-23954, GHSA-7f67-crqm-jgh7, GO-2026-4357, UBUNTU-CVE-2026-23954.