CVE-2026-63294: Root RCE via image backup.yaml symlink

Severity: critical (CVSS 9.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-08-12 · updated 2026-10-24
Weakness: CWE-59

Description

A link following vulnerability in LXD allows an attacker to achieve root command execution on the host system. During the import or unpacking of crafted image or backup archives, LXD fails to properly validate and confine the backup.yaml file when it exists as a symbolic link. An attacker can exploit this flaw by providing a malicious archive with a symlinked backup.yaml file, causing LXD to process unconfined configuration metadata and execute arbitrary commands with root privileges.

Affected products

Canonical LXD: from 4.0.0 before 4.0.12; from 5.0.0 before 5.0.8; from 5.1 before 5.21.6; from 6.0 before 6.10 — fixed in 4.0.12, 5.0.8, 5.21.6, 6.10

How to fix

Upgrade to a fixed version: Canonical LXD 4.0.12, 5.0.8, 5.21.6, 6.10. Check the vendor advisory for mitigations.

References

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