Auth bypass in Mailu

CVE-2026-86009

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.

Published · last modified .

EPSS exploit prediction

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Affected products

  • Mailu — versions < f05aeb8322e2f61096af6b089d61ba6f40587d96

Weakness classification (CWE)

References