🛡️ CVE-2026-40251 on Debian — incus
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 backup restore subsystem contains an out-of-bounds panic vulnerability caused by an invalid bounds check when indexing snapshot metadata arrays, and the same flawed pattern also appears in the migration path. When iterating through physical snapshots provided in a backup archive, the loop uses the index to look up corresponding metadata in the parsed Config.Snapshots and Config.VolumeSnapshots slices. The guard condition len(slice) >= i-1 is incorrect because it can still evaluate to true when the subsequent slice[i] access is out of bounds. An attacker can submit a backup archive that contains physical snapshot directories while supplying a tampered index.yaml with an empty or truncated snapshot metadata array, causing the daemon to index beyond the end of the metadata slice and crash. 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.
Distribution advisory
This page covers CVE-2026-40251 as tracked by Debian, for the package incus. The fix is available in version 7.0.0-1; earlier versions remain affected.
How this vulnerability can be exploited
This issue can be reached over the network, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability high.
Affected software
DEBIAN-CVE-2026-40251 is recorded against 2 packages.
- incus (fixed in 7.0.0-1)
- lxd (fixed in 5.0.2+git20231211.1364ae4-9+deb13u6)
Timeline and source
Published on 6 May 2026 and last revised on 4 August 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.
References
CVE-2026-40251 on other distributions
Each distribution ships its own build and its own fixed version. Pick the one you run:
Details
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected Packages
| Software | From version | Fixed in |
|---|---|---|
| incus | — | 7.0.0-1 |
| lxd | — | 5.0.2+git20231211.1364ae4-9+deb13u6 |
References
Similar Threats
- Medium CVE-2026-35527
- High CVE-2026-40195
- High CVE-2026-40197
- Medium CVE-2026-40243
- High CVE-2026-40251
Site Security Check
Is incus part of your stack?
DEBIAN-CVE-2026-40251 is rated CVSS 8.0 High. BotEraser scans your installation against known CVE records and tells you whether this vulnerability applies to the versions you actually run.
Scan My Site Free →No credit card required · Results in minutes
ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.