CVE-2026-23953
Incus container environment configuration newline injection
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Incus is a system container and virtual machine manager. In versions 6.20.0 and below, a user with the ability to launch a container with a custom YAML configuration (e.g a member of the ‘incus’ group) can create an environment variable containing newlines, which can be used to add additional configuration items in the container’s lxc.conf due to newline injection. This can allow adding arbitrary lifecycle hooks, ultimately resulting in arbitrary command execution on the host. Exploiting this issue on IncusOS requires a slight modification of the payload to change to a different writable directory for the validation step (e.g /tmp). This can be confirmed with a second container with /tmp mounted from the host (A privileged action for validation only). A fix is planned for versions 6.0.6 and 6.21.0, but they have not been released at the time of publication.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By GitHub_M
- 3 days later
· 3 days later
Published
- 4 days later
· 4 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.7 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N |
| NVDNVD · Analyzed | 3.1 | High8.7 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.49% · top 58% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/lxc/incus/v6GHSA-x6jc-phwx-hp32 (opens in a new tab)
References (4)
- https://github.com/lxc/incus/security/advisories/GHSA-x6jc-phwx-hp32 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/lxc/incus/blob/HEAD/internal/server/instance/drivers/driver_lxc.go#L1081 (opens in a new tab)x_refsource_MISC
- https://github.com/user-attachments/files/24473682/environment_newline_injection.sh (opens in a new tab)x_refsource_MISC
- https://github.com/user-attachments/files/24473685/environment_newline_injection.patch (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-x6jc-phwx-hp32 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-23953)Record last updated .