MajorCritical vulnerability

CVE-2026-86009 (CVSS 8.2)

NVD · officialPublished Oct 16, 2026Risk 37/100

Mailu is a mail server distributed as a set of Docker images. Prior to f05aeb8322e2f61096af6b089d61ba6f40587d96, domain managers can enable spoofing for hosted domains they do not control. A potentially malicious domain administrator enables spoofing for another hosted domain and can send emails that are authenticated with DKIM/SPF for domains they should not be able to. This vulnerability is addressed by f05aeb8322e2f61096af6b089d61ba6f40587d96.

Technical details

CVSS

8.2

AV:NetworkAC:LowPR:HighUI:None

Evidence and sources

This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.

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