CVE-2026-40873 (GCVE-0-2026-40873)
Vulnerability from cvelistv5 – Published: 2026-04-21 19:15 – Updated: 2026-04-21 19:39
VLAI
EPSS
VEX
Title
mailcow: dockerized vulnerable to stored XSS in Quarantine attachment filenames
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 19:39 UTC
CWE
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/mailcow/mailcow-dockerized/sec… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| mailcow | mailcow-dockerized |
Affected:
< 2026-03b
|
guessed |
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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