Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linuxcontainers | Incus | <= 6.0.5 |
Related Weaknesses (CWE)
References
- https://github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lProduct
- https://github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lProduct
- https://github.com/lxc/incus/security/advisories/GHSA-7f67-crqm-jgh7ExploitVendor Advisory
- https://github.com/user-attachments/files/24473599/template_arbitrary_write.shExploit
- https://github.com/user-attachments/files/24473601/templates_arbitrary_write.patPatch
FAQ
What is CVE-2026-23954?
CVE-2026-23954 is a vulnerability with a CVSS score of 8.7 (HIGH). 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 di...
How severe is CVE-2026-23954?
CVE-2026-23954 has been rated HIGH with a CVSS base score of 8.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-23954?
Check the references section above for vendor advisories and patch information. Affected products include: Linuxcontainers Incus.