CVE-2026-63297
Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge
Description
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
INFO
Published Date :
Aug. 12, 2026, 8:17 p.m.
Last Modified :
Aug. 12, 2026, 8:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | cc1ad9ee-3454-478d-9317-d3e869d708bc | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update LXD to the latest version.
- Apply vendor patches for LXD.
- Review LXD configuration merge logic.
- Monitor cross-project instance copies.
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-2026-63297.
| URL | Resource |
|---|---|
| https://github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-63297 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-2026-63297
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-2026-63297 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-63297 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.
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New CVE Received by [email protected]
Aug. 12, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/canonical/lxd', 'vendor': 'Canonical', 'product': 'LXD', 'versions': [{'status': 'affected', 'version': '5.0.0', 'lessThan': '5.0.8', 'versionType': 'semver'}, {'status': 'affected', 'version': '5.21.0', 'lessThan': '5.21.6', 'versionType': 'semver'}], 'platforms': ['Linux'], 'packageName': 'LXD', 'defaultStatus': 'unaffected'}] Added Description An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-367 Added CWE CWE-863 Added Reference https://github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4