CVE-2026-40873

mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the Quarantine details modal injects attachment filenames into HTML without escaping, allowing arbitrary HTML/JS execution. An attacker can deliver an email with a crafted attachment name so that when an admin views the quarantine item, JavaScript executes in their browser, taking over their account. Version 2026-03b fixes the vulnerability.

CVSS

No CVSS.

References

Link	Resource
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-2xjc-rg88-jvpp
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-2xjc-rg88-jvpp

Configurations

No configuration.

History

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-2026-40873

Mitre link : CVE-2026-40873

CVE.ORG link : CVE-2026-40873

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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