CVE-2026-63343
Arbitrary File Read/Write: metadata.yaml symlink in image allows host filesystem access as root
Description
Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a `metadata.yaml` symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The `exec-output` and `templates/` paths were patched in a prior release using `Lstat` rejection and `os.OpenRoot` confinement; `metadata.yaml` was not included in either patch and remains exploitable. Version 7.3.0 patches the issue.
INFO
Published Date :
Aug. 21, 2026, 3:16 p.m.
Last Modified :
Aug. 21, 2026, 3:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-63343
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Incus to version 7.3.0.
- Apply vendor patches for Incus.
- Restrict access to the instance metadata API.
- Review and validate image metadata.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-63343.
| URL | Resource |
|---|---|
| https://github.com/lxc/incus/security/advisories/GHSA-fmjx-5j3g-997p |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-63343 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-63343
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-63343 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-63343 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 21, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'lxc', 'product': 'incus', 'versions': [{'status': 'affected', 'version': '< 7.3.0'}]}] Added Description Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a `metadata.yaml` symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The `exec-output` and `templates/` paths were patched in a prior release using `Lstat` rejection and `os.OpenRoot` confinement; `metadata.yaml` was not included in either patch and remains exploitable. Version 7.3.0 patches the issue. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-73 Added Reference https://github.com/lxc/incus/security/advisories/GHSA-fmjx-5j3g-997p