Critical severity · published Apr 9, 2026
CVE-2026-34177
VM lowlevel restriction bypass via raw.apparmor and raw.qemu.conf
9.1
CVSS
0.4%
EPSS
No
On KEV
Description
Canonical LXD versions 4.12 through 6.7 contain an incomplete denylist in isVMLowLevelOptionForbidden (lxd/project/limits/permissions.go), which omits raw.apparmor and raw.qemu.conf from the set of keys blocked under the restricted.virtual-machines.lowlevel=block project restriction. A remote attacker with can_edit permission on a VM instance in a restricted project can inject an AppArmor rule and a QEMU chardev configuration that bridges the LXD Unix socket into the guest VM, enabling privilege escalation to LXD cluster administrator and subsequently to host root.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LX
lxd · Canonical
4.12.0 before 5.0.7; 5.1.0 before 5.21.5; 6.0.0 before 6.8.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34177
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34177
Issue Tracking
https://github.com/canonical/lxd/pull/17909
Third Party Advisory
https://github.com/canonical/lxd/security/advisories/GHSA-fm2x-c5qw-4h6f
More from lxd
9.9
CVE-2026-87799
Arbitrary file write on LXD host via symlink in migration stream
9.9
CVE-2026-85526
Path traversal via Btrfs optimized-backup subvolumes[].path enables root file/dir manipulation in LXD
9.9
CVE-2026-66897
Instance template path traversal allows arbitrary host file write as root
9.9
CVE-2026-66898
Path traversal via unvalidated instance name in backup tarball restore enables root file write / RCE
9.9
CVE-2026-63293
Arbitrary File Read/Write: metadata.yaml symlink in image allows host filesystem access as root