CVE-2026-40872 Details
Description
mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the admin dashboard's Autodiscover logs render the EMailAddress value (logged as the "user" field) without HTML escaping. By submitting an unauthenticated Autodiscover request with a crafted EMailAddress containing HTML/JS, the payload is stored in Redis and executed when an admin views the Autodiscover logs. Version 2026-03b fixes the vulnerability.
A stored cross-site scripting vulnerability has been identified in mailcow: dockerized versions prior to 2026-03b. The issue arises in the admin dashboard's Autodiscover logs, where the EMailAddress value is rendered without proper HTML escaping. This flaw allows an unauthenticated attacker to send a crafted Autodiscover request that injects HTML or JavaScript. The malicious payload is stored in Redis and executed when an admin views the Autodiscover logs.
Users can update to mailcow: dockerized version 2026-03b or later to address this vulnerability.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Apr 21, 2026CISA-ADP
Assessed Apr 22, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgm | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgm | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-79 | Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') | [email protected] |
| CWE-80 | Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| mailcow: dockerized | < 2026-03b |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Apr 22, 2026 | CVE Modified | CISA-ADP |
| Apr 21, 2026 | New CVE Received | [email protected] |