CVE-2026-40874: CWE-284: Improper Access Control in mailcow mailcow-dockerized
mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, no administrator verification takes place when deleting Forwarding Hosts with `/api/v1/delete/fwdhost`. Any authenticated user can call this API. Checks are only applied for edit/add actions, but deletion can still significantly disrupt the mail service. Version 2026-03b fixes the vulnerability.
AI Analysis
Technical Summary
mailcow-dockerized, an open source groupware/email suite, had an access control flaw (CWE-284) in versions before 2026-03b where the API endpoint for deleting Forwarding Hosts did not verify administrator privileges. This allowed any authenticated user to delete forwarding hosts, potentially disrupting mail operations. The vulnerability was addressed and fixed in version 2026-03b. The CVSS 4.0 score is 6.0 (medium severity), reflecting network attack vector, high attack complexity, and partial privileges required.
Potential Impact
Any authenticated user on affected versions can delete Forwarding Hosts without proper authorization, which can significantly disrupt mail service functionality. There is no indication of remote code execution or data disclosure, but the disruption of mail forwarding can impact availability and mail delivery.
Mitigation Recommendations
Upgrade mailcow-dockerized to version 2026-03b or later where this vulnerability is fixed. No other official remediation or temporary fix is documented. Patch status is not explicitly confirmed in vendor advisories, but the description states the issue is fixed in 2026-03b, so upgrading is the recommended action.
CVE-2026-40874: CWE-284: Improper Access Control in mailcow mailcow-dockerized
Description
mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, no administrator verification takes place when deleting Forwarding Hosts with `/api/v1/delete/fwdhost`. Any authenticated user can call this API. Checks are only applied for edit/add actions, but deletion can still significantly disrupt the mail service. Version 2026-03b fixes the vulnerability.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
mailcow-dockerized, an open source groupware/email suite, had an access control flaw (CWE-284) in versions before 2026-03b where the API endpoint for deleting Forwarding Hosts did not verify administrator privileges. This allowed any authenticated user to delete forwarding hosts, potentially disrupting mail operations. The vulnerability was addressed and fixed in version 2026-03b. The CVSS 4.0 score is 6.0 (medium severity), reflecting network attack vector, high attack complexity, and partial privileges required.
Potential Impact
Any authenticated user on affected versions can delete Forwarding Hosts without proper authorization, which can significantly disrupt mail service functionality. There is no indication of remote code execution or data disclosure, but the disruption of mail forwarding can impact availability and mail delivery.
Mitigation Recommendations
Upgrade mailcow-dockerized to version 2026-03b or later where this vulnerability is fixed. No other official remediation or temporary fix is documented. Patch status is not explicitly confirmed in vendor advisories, but the description states the issue is fixed in 2026-03b, so upgrading is the recommended action.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-15T15:57:41.718Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e7d08919fe3cd2cdf3fb1c
Added to database: 4/21/2026, 7:31:21 PM
Last enriched: 4/21/2026, 7:47:27 PM
Last updated: 4/22/2026, 7:40:58 AM
Views: 11
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