CVE-2026-23954
CVE-2026-23954 is a high-severity vulnerability in Linuxcontainers Incus with a CVSS 3.x base score of 8.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.
Key facts
- Severity: High (CVSS 3.x base score 8.7)
- EPSS exploit prediction: 1% (50th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-3803
- Weakness: CWE-22
- Affected product: Linuxcontainers Incus
- Published:
- Last modified:
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.
Frequently asked questions
- What is 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.
- How severe is CVE-2026-23954?
- CVE-2026-23954 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
- Is CVE-2026-23954 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-23954?
- CVE-2026-23954 affects Linuxcontainers Incus. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-23954?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-23954 have an EU (EUVD) identifier?
- Yes. CVE-2026-23954 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3803.
- When was CVE-2026-23954 published?
- CVE-2026-23954 was published on 2026-01-22 and last updated on 2026-06-17.
References
- https://github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lxc.go#L7215
- https://github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lxc.go#L7294
- https://github.com/lxc/incus/security/advisories/GHSA-7f67-crqm-jgh7
- https://github.com/user-attachments/files/24473599/template_arbitrary_write.sh
- https://github.com/user-attachments/files/24473601/templates_arbitrary_write.patch
Affected products (1)
- cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*
More vulnerabilities in Linuxcontainers Incus
- CVE-2026-33945 — Critical (CVSS 9.9): Incus is a system container and virtual machine manager. Incus instances have an option to provide credentials to…
- CVE-2026-33897 — Critical (CVSS 9.9): Incus is a system container and virtual machine manager. Prior to version 6.23.0, instance template files can be used…
- CVE-2026-33898 — High (CVSS 8.8): Incus is a system container and virtual machine manager. Prior to version 6.23.0, the web server spawned by `incus…
- CVE-2026-23953 — High (CVSS 8.7): Incus is a system container and virtual machine manager. In versions 6.20.0 and below, a user with the ability to…
- CVE-2026-33711 — High (CVSS 7.8): Incus is a system container and virtual machine manager. Incus provides an API to retrieve VM screenshots. That API…
- CVE-2025-64507 — High (CVSS 7.8): Incus is a system container and virtual machine manager. An issue in versions prior to 6.0.6 and 6.19.0 affects any…
All CVEs affecting Linuxcontainers Incus →
Other CWE-22 (Path Traversal) vulnerabilities
- CVE-2026-48282 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Limitation of a Pathname to a Restricted…
- CVE-2026-54917 — Critical (CVSS 10.0): SeaweedFS is a distributed storage system for object storage (S3), file systems, and Iceberg tables. Prior to 4.30, the…
- CVE-2026-11429 — Critical (CVSS 10.0): Two endpoints in the Vault Service ScriptsController, shared by Altium Enterprise Server and Altium 365, accept file…
- CVE-2026-34909 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices to…
- CVE-2026-7411 — Critical (CVSS 10.0): In Eclipse BaSyx Java Server SDK versions prior to 2.0.0-milestone-10, inadequate path normalization in the Submodel…
- CVE-2026-36767 — Critical (CVSS 10.0): A path traversal vulnerability in the /content/images/add endpoint of shopizer v3.2.5 allows attackers write arbitrary…