Medium severity · published Jun 26, 2026
CVE-2026-9639
Authenticated Denial of Service via Malicious Backup Tarball in LXD
6.5
CVSS
0.5%
EPSS
No
On KEV
Description
Nil-pointer dereference in CreateCustomVolumeFromBackup in LXD up to version 6.8 and 5.21 on Linux allows an authenticated user with can_create_storage_volumes permissions to cause a denial of service via a specially crafted custom-volume backup tarball that omits the expires_at snapshot field.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LX
LXD · Canonical
5.21.0 before 5.21.5; 6.0 before 6.9 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-9639
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-9639
Issue Tracking
https://github.com/canonical/lxd/pull/18320
Issue Tracking
https://github.com/canonical/lxd/pull/18390
Exploit
https://github.com/canonical/lxd/security/advisories/GHSA-j93m-3j9p-m5m8
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