CVE-2026-66797: Apache CloudStack: Unauthorised comment creation and disclosure

Published Aug 21, 2026
·
Updated

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 Software

1 affected component
Apache CloudStack>=4.15.0.0<=4.20.3.0, >=4.21.0.0<=4.22.1.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Apache CloudStack to a version that resolves this vulnerability.

    Fixed in 4.20.3.1
  2. Upgrade

    Upgrade Apache CloudStack to a version that resolves this vulnerability.

    Fixed in 4.22.1.1

Event History

Aug 21, 2026
CVE Published
via MITRE·08:21 AM
Data Sourced
via MITRE·08:21 AM
DescriptionWeakness

Frequently Asked Questions

1

Who can exploit this issue?

Any authenticated CloudStack user can exploit it. The attacker needs the UUID of an entity they do not own.

2

Which deployments are affected?

Apache CloudStack versions 4.15.0.0 through 4.20.3.0 and 4.21.0.0 through 4.22.1.0 are affected.

3

What can an attacker do with a target entity UUID?

They can create annotations on an entity they do not own and disclose existing annotations or comments associated with that entity.

4

What is the remediation?

Upgrade to Apache CloudStack 4.20.3.1 or 4.22.1.1, or a later version.

Contact

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