CVE-2025-66172Network attack vector

Authenticated cross-tenant backup access via missing ownership check

Published May 8, 2026 · Updated May 8, 2026

Improper authorization in the Apache CloudStack Backup plugin 4.21.0.0 through 4.22.0.0 allows remote authenticated users to restore others' backups. The affected volume-restore API fails to enforce tenant ownership of the requested backup before creating a volume from it. This requires an enabled Backup plugin and access to the affected APIs; attachment to the caller's VM exposes the copied volume contents without altering the source backup.

CVSS severity8.1
High
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in the Apache CloudStack Backup plugin 4.21.0.0 through 4.22.0.0 allows remote authenticated users to restore others' backups. The affected volume-restore API fails to enforce tenant ownership of the requested backup before creating a volume from it. This requires an enabled Backup plugin and access to the affected APIs; attachment to the caller's VM exposes the copied volume contents without altering the source backup.

The record

CVE
CVE-2025-66172
Published
May 8, 2026
Updated
May 8, 2026
Vendor
The Apache Software Foundation
Product
Apache CloudStack
Classifications
CWE-359, T1530
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 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.

  1. Affected versionversion=4.21.0.0 <=4.22.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Apache Software Foundation · Apache CloudStackversion=4.21.0.0 <=4.22.0.0

Published CVSS scores

8.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-359Exposure of Private Personal Information to an Unauthorized Actor
T1530Data from Cloud Storage

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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