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 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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgm
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgm

Configurations

No configuration.

History

22 Apr 2026, 14:17

Type	Values Removed	Values Added
References	~~() https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgm -~~	() https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgm -

21 Apr 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-21 20:17

Updated : 2026-04-22 21:02

NVD link : CVE-2026-40872

Mitre link : CVE-2026-40872

CVE.ORG link : CVE-2026-40872

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-80

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

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