Canonical LXD up to 5.21.4/6.8 on Linux null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Canonical LXD up to 5.21.4/6.8 on Linux. It has been rated as problematic. Affected by this issue is some unknown functionality. Performing a manipulation results in null pointer dereference. This vulnerability is cataloged as CVE-2026-9639. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Canonical LXD up to 5.21.4/6.8 on Linux. It has been classified as critical. This affects an unknown function. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-9639 since 05/26/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 323599 (Linux Distros Unpatched Vulnerability : CVE-2026-9639), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.21.5 or 6.9 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (323599). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.3

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (canonical): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 323599
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-9639

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: LXD 5.21.5/6.9
Patch: github.com

Timelineinfo

05/26/2026 CVE reserved
06/26/2026 +31 days Advisory disclosed
06/26/2026 +0 days VulDB entry created
06/29/2026 +3 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-j93m-3j9p-m5m8
Status: Confirmed

CVE: CVE-2026-9639 (🔒)
GCVE (CVE): GCVE-0-2026-9639
GCVE (VulDB): GCVE-100-374199

Entryinfo

Created: 06/26/2026 18:51
Updated: 06/29/2026 05:44
Changes: 06/26/2026 18:51 (66), 06/29/2026 05:44 (2)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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