CVE-2026-40197
CVE-2026-40197 is a NULL Pointer Dereference vulnerability in github.com/lxc/incus/v6/cmd/incusd. O3 Security confirms whether CVE-2026-40197 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Incus nil-pointer dereference in custom volume import allows denial of service
Real-World Exposure
github.com/lxc/incus/v6/cmd/incusdReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Incus is a system container and virtual machine manager. In versions before 7.0.0, missing validation logic in the storage volume import logic allows an authenticated user with access to the storage volume feature to cause the Incus daemon to crash. The custom volume backup import subsystem contains a nil-pointer dereference vulnerability during import operations. In the snapshot import loop, the daemon iterates over entries from srcBackup.Config.VolumeSnapshots and assumes that each slice element is initialized, then dereferences fields such as Name, Config, Description, CreatedAt, and ExpiresAt without first validating the element itself. Because the yaml unmarshaler accepts explicit null array elements from an attacker-controlled index.yaml and converts them into nil pointers inside the slice, an attacker can supply a backup archive containing a null entry in the volume_snapshots array. This causes a nil-pointer dereference during custom volume import and terminates the daemon, resulting in denial of service on the affected node. Repeated use of this issue can be used to keep Incus offline, causing a denial of service. This issue is fixed in version 7.0.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/lxc/incus/v6/cmd/incusd | all versions | 7.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/lxc/incus/v6/cmd/incusd. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/lxc/incus/v6/cmd/incusd to 7.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-40197 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-40197 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-40197. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-40197 in your dependencies?
O3 detects CVE-2026-40197 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.