Description
An improper sanitization of the compression_algorithm parameter in Canonical LXD allows an authenticated, unprivileged user to execute commands as the LXD daemon on the LXD server via API calls to the image and backup endpoints. This issue affected LXD from 4.12 through 6.6 and was fixed in the snap versions 5.0.6-e49d9f4 (channel 5.0/stable), 5.21.4-1374f39 (channel 5.21/stable), and 6.7-1f11451 (channel 6.0 stable). The channel 4.0/stable is not affected as it contains version 4.0.10.
Affected products
canonical: lxd
References6
- discourse.ubuntu.com/t/lxd-authenticated-remote-code-execution-… Issue TrackingExploitVendor Advisory
- github.com/canonical/lxd/security/advisories/GHSA-4rmf-rcp8-2r9g Vendor AdvisoryExploit
- github.com/canonical/lxd/security/advisories/GHSA-4rmf-rcp8-2r9g Vendor AdvisoryExploit
- github.com/canonical/lxd/commit/043696a13171ace7dd4c2b32d34ce03… Patch
- github.com/canonical/lxd/commit/7046979645c2ce1b63b2f9e60ddf6cb… Patch
- github.com/canonical/lxd/commit/b7b411caf5c4971bfe2386c72128f44… Patch
Metrics
- CVSS 3.1
-
9.9
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - CVSS 4.0
-
9.4
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 56 · as of 12 November 2026
- CWE
- CWE-78
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