HIGHCVE-2026-40873Published Modified CNA GitHub_M
CVE-2026-40873: mailcow: dockerized vulnerable to stored XSS in Quarantine attachment filenames
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.
Metrics
- CVSS v4.0
- 8.9
- Severity
- HIGH
- Fixed in
- —
- Affected Products
- 1
Affected packages
- mailcow / mailcow-dockerized< 2026-03b
CVSS Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:N