CVE-2026-40872

CRITICAL EPSS 19.7%

Published Apr 21, 20262mo ago · Modified Jun 17, 20261w ago

9.3 CVSS 4.0

Critical

Published Apr 21, 2026 2mo ago

Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score

9.3

Exploitability

—

Impact

—

Vector string

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

Attack Vector Network

Attack Complexity Low

Privileges Required None

User Interaction P

Scope X

Threat Intelligence

EPSS Exploit Probability

19.7% percentile

Exploit & Patch Status

No Known Exploit

No Patch Available

Weaknesses 2

CWE-79 Cross-site Scripting Injection

CWE-80

References 1

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

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.