CVE-2026-66797
Published:August 21, 2026
Updated:September 24, 2026
Improper access control in CloudStack's annotation functionality allows unauthorized comment creation and disclosure.
The addAnnotation and listAnnotation APIs perform an ownership check when an entity's UUID is specified, but fail to honor its result correctly. This lets any authenticated user write annotations to, and disclose existing annotations/comments on, an entity they don't own by simply supplying its UUID.
This issue affects Apache CloudStack: from 4.15.0.0 through 4.20.3.0 and from 4.21.0.0 through 4.22.1.0.
Users are recommended to upgrade to version 4.20.3.1 or 4.22.1.1 or later, which fixes the issue.
Affected Packages
https://github.com/apache/cloudstack.git (GITHUB):
Affected version(s) >=4.16.0.0 <4.20.3.1Fix Suggestion:
Update to version 4.20.3.1https://github.com/apache/cloudstack.git (GITHUB):
Affected version(s) >=4.21.0.0 <4.22.1.1Fix Suggestion:
Update to version 4.22.1.1Related Resources (3)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.4
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Improper Access Control
EPSS
Base Score:
0.26