Path Traversal in Linuxcontainers Incus
CVE-2026-23954
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.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.008 (54.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: +0.000
Affected products
- Linuxcontainers Incus
- Lxc Incus — versions >= 6.1.0, <= 6.20.0, <= 6.0.5
Weakness classification (CWE)
References
- github.com/lxc/incus/security/advisories/GHSA-7f67-crqm-jgh7 (Exploit, Vendor Advisory)
- github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lxc.go (Product)
- github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lxc.go (Product)
- github.com/user-attachments/files/24473599/template_arbitrary_write.sh (Exploit)
- github.com/user-attachments/files/24473601/templates_arbitrary_write.patch (Patch)
Frequently asked questions
- What is CVE-2026-23954?
- CVE-2026-23954 is a high-severity vulnerability in Linuxcontainers Incus, classified under Path Traversal. CVSS score: 8.7/10. Published 2026-01-22.
- How severe is CVE-2026-23954?
- High severity. CVSS v3 base score is 8.7 out of 10.