mailcow mailcow-dockerized prior 2026-03b Mail Service access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.2$0-$5k0.00

Summaryinfo

A vulnerability was found in mailcow mailcow-dockerized. It has been rated as critical. Affected by this vulnerability is an unknown functionality of the component Mail Service. The manipulation leads to access control. This vulnerability is traded as CVE-2026-40874. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in mailcow mailcow-dockerized. This issue affects an unknown function of the component Mail Service. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-40874 since 04/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1068 for this issue.

Upgrading to version 2026-03b eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: mailcow-dockerized 2026-03b

Timelineinfo

04/15/2026 CVE reserved
04/21/2026 +6 days Advisory disclosed
04/21/2026 +0 days VulDB entry created
04/21/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-jjxh-rm7p-hjc3
Status: Confirmed

CVE: CVE-2026-40874 (🔒)
GCVE (CVE): GCVE-0-2026-40874
GCVE (VulDB): GCVE-100-358589
scip Labs: https://www.scip.ch/en/?labs.20171019

Entryinfo

Created: 04/21/2026 22:35
Changes: 04/21/2026 22:35 (68)
Complete: 🔍
Cache ID: 216::103

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