Cross-tenant annotation disclosure and creation via ignored ownership
Published Aug 21, 2026 · Updated Aug 21, 2026
Access control flaw in CloudStack 4.16.0.0 through 4.20.3.0 and 4.21.0.0 through 4.22.1.0 lets remote authenticated users read and create annotations. The addAnnotation and listAnnotation APIs call an ownership check for a supplied entity UUID but continue when it fails, accepting a write or returning stored comments. Exploitation requires a remote authenticated CloudStack account and another tenant entity's UUID; consequences are limited to annotation disclosure and creation.
Summary
What happened
Access control flaw in CloudStack 4.16.0.0 through 4.20.3.0 and 4.21.0.0 through 4.22.1.0 lets remote authenticated users read and create annotations. The addAnnotation and listAnnotation APIs call an ownership check for a supplied entity UUID but continue when it fails, accepting a write or returning stored comments. Exploitation requires a remote authenticated CloudStack account and another tenant entity's UUID; consequences are limited to annotation disclosure and creation.
The record
- CVE
- CVE-2026-66797
- Published
- Aug 21, 2026
- Updated
- Aug 21, 2026
- Vendor
- The Apache Software Foundation
- Product
- Apache CloudStack
- Classifications
- CWE-284, T1213
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 21, 2026CVE publishedPublication date reported by the CVE source.
- Aug 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4.16.0.0 <=4.20.3.0
- Affected versionversion=4.21.0.0 <=4.22.1.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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