CVE-2026-33945: Github.com/lxc/incus/v6 Incus Has An Abitrary File Vulnerability

CRITICAL
Advisory Identifier: GHSA-q4q8-7f2j-9h9f
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CVSS 9.9
CWE-22
Published
Advisory Summary

CVE-2026-33945 is a CRITICAL (CVSS 9.9) incus has an abitrary file vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting Github.com/lxc/incus/v6 libraries in the Go ecosystem. The issue involves incus has an abitrary file write through its systemd-creds options. Remediation is available by upgrading affected packages to version 6.23.0.

CVE-2026-33945 at a Glance

CVE Identifier CVE-2026-33945
GHSA Identifier GHSA-q4q8-7f2j-9h9f
Severity CRITICAL
CVSS v3.1 Base Score 9.9
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product Github.com/lxc/incus/v6
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 9.9

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-33945

To remediate this vulnerability, upgrade all affected Github.com/lxc/incus/v6 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/lxc/incus/v6 fixed: 6.23.0 
Upgrade github.com/lxc/incus/v6 to 6.23.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for github.com/lxc/incus/v6

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-33945, inspect your project dependencies for Github.com/lxc/incus/v6:

inspect dependencies for github.com/lxc/incus/v6

Analyze the terminal output to locate any version of Github.com/lxc/incus/v6 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 6.23.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'), where the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. In Github.com/lxc/incus/v6, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary Incus instances have an option to provide credentials to systemd in the guest. For containers, this is handled through a shared directory. An attacker can use the name of a systemd credential to escape that directory and overwrite arbitrary files on the host system. This can in turn be used to perform local privilege escalation or cause a DoS. ### Details An attacker can set a configuration key named something like `systemd.credential.../../../../../../root/.bashrc` to cause Incus to write outside of the `credentials` directory associated with the container. This makes use of the fact that the Incus syntax for such credentials is `systemd.credential.XYZ` where `XYZ` can itself contain more periods. While it's not possible to read any data this way, it's possible to write to arbitrary files as root, enabling both privilege escalation and denial of service attacks. ### Credit This issue was discovered and reported by the team at [7asecurity](https://7asecurity.com/)

CVE-2026-33945 Affected Github.com/lxc/incus/v6 Versions

1 component(s)
Fixed Versions:
6.23.0
Product / Package Ecosystem Affected Versions Fixed Version
github.com/lxc/incus/v6
golang/github.com/lxc/incus/v6
Go
< 6.23.0
6.23.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/lxc/incus/security/advisories/GHSA-q4q8-7f2j-9h9f
NVD — CVE-2026-33945 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33945
Security Fix Commit FIX COMMIT
https://github.com/lxc/incus/commit/f74199f9983e2ce78f2b78b6d765c6635b229c82
Github.com/lxc/incus/v6 Source Repository REPOSITORY
https://github.com/lxc/incus

Frequently Asked Questions

What is CVE-2026-33945?
CVE-2026-33945 is a security vulnerability in Github.com/lxc/incus/v6 involving Incus has an abitrary file write through its systemd-creds options under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which Github.com/lxc/incus/v6 versions are affected?
Affected versions include releases prior to 6.23.0 across affected packages: github.com/lxc/incus/v6.
What version fixes CVE-2026-33945?
Upgrading to 6.23.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/lxc/incus/v6 affected?
Yes, github.com/lxc/incus/v6 is affected in releases prior to 6.23.0. Upgrade your dependency to 6.23.0 or later.
What is the CVSS score of CVE-2026-33945?
CVE-2026-33945 has a CVSS v3.1 base score of 9.9 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
What CWE is associated with CVE-2026-33945?
CVE-2026-33945 is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.).
How can I check Go dependencies for CVE-2026-33945?
Run the dependency tree command: 'inspect dependencies for github.com/lxc/incus/v6'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-q4q8-7f2j-9h9f",
  "modified" : "2026-03-27T17:22:32Z",
  "published" : "2026-03-27T17:22:32Z",
  "aliases" : [ "CVE-2026-33945" ],
  "summary" : "Incus has an abitrary file write through its systemd-creds options",
  "details" : "### Summary\nIncus instances have an option to provide credentials to systemd in the guest. For containers, this is handled through a shared directory.\nAn attacker can use the name of a systemd credential to escape that directory and overwrite arbitrary files on the host system.\n\nThis can in turn be used to perform local privilege escalation or cause a DoS.\n\n### Details\nAn attacker can set a configuration key named something like `systemd.credential.../../../../../../root/.bashrc` to cause Incus to write outside of the `credentials` directory associated with the container. This makes use of the fact that the Incus syntax for such credentials is `systemd.credential.XYZ` where `XYZ` can itself contain more periods.\n\nWhile it's not possible to read any data this way, it's possible to write to arbitrary files as root, enabling both privilege escalation and denial of service attacks.\n\n### Credit\nThis issue was discovered and reported by the team at [7asecurity](https://7asecurity.com/)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/lxc/incus/v6"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "6.23.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/lxc/incus/security/advisories/GHSA-q4q8-7f2j-9h9f"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33945"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/lxc/incus/commit/f74199f9983e2ce78f2b78b6d765c6635b229c82"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/lxc/incus"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-27T17:22:32Z",
    "nvd_published_at" : "2026-03-27T00:16:23Z"
  }
}