CVE-2026-40872 (GCVE-0-2026-40872)

Vulnerability from cvelistv5 – Published: 2026-04-21 19:14 – Updated: 2026-04-22 13:37
VLAI
Title
mailcow: dockerized vulnerable to stored XSS in autodiscover logs email address field
Summary
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.
Severity
9.3 (Critical)
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
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-22 13:36 UTC
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)
Assigner
References
Impacted products
Vendor Product Version CPE status
mailcow mailcow-dockerized Affected: < 2026-03b
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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