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CVE-2026-63297 (GCVE-0-2026-63297)

Vulnerability from cvelistv5 – Published: 2026-08-12 19:25 – Updated: 2026-08-13 14:29
VLAI
Title
Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge
Summary
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.
Severity
9.9 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 14:28 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
  • CWE-863 - Incorrect Authorization
Assigner
References
URL Tags
https://github.com/canonical/lxd/security/advisor… vdb-entryvendor-advisory
Impacted products
Vendor Product Version CPE status
Canonical LXD Affected: 5.0.0 , < 5.0.8 (semver)
Affected: 5.21.0 , < 5.21.6 (semver)
guessed Create a notification for this product.
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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.