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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.
Show details on NVD website
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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.

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  • 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.
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  • 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.


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