CVE-2026-40872

published 2026-04-21

CVE-2026-40872: 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…

Priority P3 52 critical 9.3 CVSS 4.0

AV N AC L AT N PR N UI P VC H VI H VA H SC H SI H SA N E X CR X IR X AR X MAV X MAC X MAT X MPR X MUI X MVC X MVI X MVA X MSC X MSI X MSA X S X AU X R X V X RE X U X

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.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
mailcow	mailcow-dockerized	< 2026-03b	2026-03b

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CWE-79 CWE-80