CVE-2026-40197 Incus nil-pointer dereference in custom volume import allows denial of service

What is CVE-2026-40197?

CVE-2026-40197 is a high-severity vulnerability in lxc incus, published on 6 May 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. 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.

Weakness: CWE-476

Which versions are affected by CVE-2026-40197?

5 open source packages ship an affected version, including github.com/lxc/incus/v6/cmd/incusd, github.com/lxc/incus and github.com/lxc/incus/v6. It affects 1 product.

Products include Linuxcontainers Incus.

How do I fix CVE-2026-40197?

Upgrade github.com/lxc/incus/v6/cmd/incusd to 7.0.0 or later.

Is CVE-2026-40197 being exploited?

There is no known exploitation of CVE-2026-40197 in the wild and no public exploit code.

Other vulnerabilities in lxc incus

• CVE-2026-33897 Incus vulnerable to arbitrary file read and write through pongo templates Critical 10.0
• CVE-2026-33945 Abitrary file write through systemd-creds option Critical 10.0
• CVE-2026-33898 Local Incus UI web server vulnerable to nuthentication bypass High 8.8
• CVE-2026-23953 Incus container environment configuration newline injection High 8.7
• CVE-2026-23954 Incus container image templating arbitrary host file read and write High 8.7

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2026-40197, GHSA-r7w7-mmxr-47r9, GO-2026-5612, UBUNTU-CVE-2026-40197.