CVE-2026-40873: high-severity vulnerability in mailcow-dockerized
mailcow: dockerized vulnerable to stored XSS in Quarantine attachment filenames
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.9epss 0.4%
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:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:N
Affected products
mailcow · mailcow-dockerizedRelated CVEs — mailcow-dockerized
In the same product, most dangerous first.
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