CVE-2026-62941 Incus: Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge
Attackers can bypass project restrictions during cross-project instance copies by exploiting a time-of-check time-of-use race condition in configuration merging.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-62941?
CVE-2026-62941 is a critical vulnerability in lxc incus, published on 21 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Incus is a system container and virtual machine manager. Prior to version 7.3.0, when copying an instance across projects, the project restriction check (`AllowInstanceCreation`) runs BEFORE the source instance's configuration is merged into the request. Dangerous configuration keys (including `security.privileged`, `raw.lxc`, `raw.apparmor`) from the source instance are merged AFTER the check passes, bypassing all project restrictions on the target project. Version 7.3.0 patches the issue.
Weakness: CWE-863
Which versions are affected by CVE-2026-62941?
How do I fix CVE-2026-62941?
Upgrade to a fixed version.
Is CVE-2026-62941 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-62941 exists.
Sources
Also known as DEBIAN-CVE-2026-62941, GHSA-mq9x-prm8-3vpw, UBUNTU-CVE-2026-62941.