CVE-2026-41684 Incus: Nil Dereferences on Restore via Malformed YAML

What is CVE-2026-41684?

CVE-2026-41684 is a medium-severity vulnerability in lxc incus, published on 7 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. Prior to version 7.0.0, backup.GetInfo() trusts the inline backup/index.yaml config when present and only falls back to parsing the legacy backup/container/backup.yaml file if result.Config == nil. As a result, an archive can carry a valid inline config that passes the initial import preflight while also carrying a malformed legacy backup/container/backup.yaml file that is reparsed later from the restored file system. ParseConfigYamlFile() accepts YAML documents with no container section, and multiple downstream consumers then dereference. Container without checking for nil. Confirmed examples in the instance restore and import flow include backup.UpdateInstanceConfig() and internalImportFromBackup(). An authenticated user with permission to import instance backups may be able to crash the Incus daemon with a crafted backup archive whose inline backup/index.yaml is valid but whose extracted legacy backup.yaml omits container. The crash occurs in the restore path after archive extraction has begun. This issue has been patched in version 7.0.0.

Weakness: CWE-476

Which versions are affected by CVE-2026-41684?

4 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-2026-41684?

Upgrade to a fixed version.

Is CVE-2026-41684 being exploited?

There is no known exploitation of CVE-2026-41684 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-2026-41684, GHSA-x5r6-jr56-89pv, GO-2026-5742, UBUNTU-CVE-2026-41684.