SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-66797

Improper access control in CloudStack's annotation functionality allows unauthorized comment creation and disclosure.

MEDIUM 5.4EPSS 0.46%

Does this matter?

Lower severity and a low EPSS score (0.46%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS
0.46% probability · 40th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-284
Affected
apache/cloudstack
Source
security@apache.org
EPSS trend
0%3%5%27 October 2026: 0.46%27 October 202627 October 2026

EPSS 0.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.