# CVE-2026-28384: Canonical LXD improper sanitization in compression_algorithm parameter

Source: https://junglewise.ai/threats/cve-2026-28384-canonical-lxd-improper-sanitization-in-compression-algorithm  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-03-12. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-28384 · Severity: critical · CVSS 9.9 · Published 2026-03-12

LXD is a container management system used to deploy and manage virtual machines and containers across infrastructure. An authenticated user with valid credentials can exploit improper input validation to execute arbitrary commands as the LXD daemon, potentially gaining full control of the container host. This vulnerability affects LXD versions from 4.12 onwards where unprivileged users were restricted by the project feature.

Technologies: [Canonical LXD](https://junglewise.ai/threats/technologies/lxd). Vendors: [Canonical](https://junglewise.ai/threats/vendors/canonical).

## Quick answers

**Is CVE-2026-28384 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-28384 being exploited in the wild.

**How severe is CVE-2026-28384?** Critical severity, with a CVSS score of 9.9, published 12 March 2026.

**Which products and versions are affected?** Canonical LXD 4.12 through 6.6.

**Is there a fix for CVE-2026-28384?** A patch was published on 2026-03-11: Patches released: 5.0.6-e49d9f4 (5.0/stable), 5.21.4-1374f39 (5.21/stable), 6.7-1f11451 (6.0/stable) Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-28384 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-28384?** Check whether you run Canonical LXD at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a command injection flaw in the compression_algorithm parameter handling for the image and backup API endpoints. The affected code fails to properly sanitize user-supplied compression algorithm values before passing them to the backend processor, which prepends "-c" to create shell commands. An authenticated attacker can craft a payload like "bash \"sleep 1\"" that gets processed as "bash -c \"sleep 1\"", achieving arbitrary command execution as the LXD daemon. The issue exists in LXD versions 4.12 through 6.6; fixed versions include 5.0.6-e49d9f4, 5.21.4-1374f39, 6.7-1f11451, and later. No authentication bypass is required; the attacker must possess valid LXD credentials.

## Affected products

- Canonical LXD 4.12 through 6.6

## Timeline

- 2026-03-12: disclosed: Vulnerability CVE-2026-28384 disclosed; fixes available for snap channels 5.0, 5.21, and 6.0
- 2026-03-11: patched: Patches released: 5.0.6-e49d9f4 (5.0/stable), 5.21.4-1374f39 (5.21/stable), 6.7-1f11451 (6.0/stable)

## References

- [https://discourse.ubuntu.com/t/lxd-authenticated-remote-code-execution-fixes-available/78365](https://discourse.ubuntu.com/t/lxd-authenticated-remote-code-execution-fixes-available/78365)
- [https://github.com/canonical/lxd/commit/043696a13171ace7dd4c2b32d34ce039ab629052](https://github.com/canonical/lxd/commit/043696a13171ace7dd4c2b32d34ce039ab629052)

## Related threats

- [LXD project restriction bypass in instance copy](https://junglewise.ai/threats/lxd-has-project-restriction-bypass-in-instance-copy-across-projects-48d466e0)
- [Canonical LXD improper certificate validation in HTTPS listener](https://junglewise.ai/threats/cve-2026-112816-improper-certificate-validation-in-the-https-listener-in)
- [Canonical LXD custom storage volume authorization bypass](https://junglewise.ai/threats/cve-2026-97335-incorrect-authorization-in-the-custom-storage-volume-creation)
- [Canonical LXD arbitrary file write via symlink in migration stream](https://junglewise.ai/threats/cve-2026-87799-improper-link-resolution-in-the-migration-receive-path-in)
- [Canonical LXD improper symlink resolution in recursive file pull](https://junglewise.ai/threats/cve-2026-87798-improper-link-resolution-in-the-recursive-file-pull-feature-of)