CVE-2026-66797

Medium

Description

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.

SeverityMedium
CVSS5.4
Exploit probability—
ProductApache Cloudstack
PublishedAug 21, 2026
First seenAug 21, 2026

How to fix

Update
  • apache cloudstack4.20.3.1, 4.22.1.1 or later

Affected products

ProductAffected versionsFixed in
apache cloudstack4.15.0.0 ≤ v < 4.20.3.1, 4.21.0.0 ≤ v < 4.22.1.14.20.3.1, 4.22.1.1

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