CVE-2026-40872
criticalpriority · track · 0EPSS 0.004 · 30 %ileEUEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.6–9.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-40872cnnvd
- https://github.com/mailcow/mailcow-dockerized/releasesPatchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-40872cnnvd
- https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgmenisa_euvd
- https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-f9xf-vc72-rcgmnvd
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