CVE-2026-85751 | BDVDB-2026-377441 Detail
MailuMailu
Description#
Mailu is a mail server distributed as a set of Docker images. From Mailu 2.0 until 2024.06.55 and prior to Mailu helm-charts 2.7.3, deployments with PROXY_AUTH_WHITELIST configured but REAL_IP_HEADER unset trusted a client-controlled X-Forwarded-By header for header-based proxy authentication. The proxy_hide_header directive in the nginx template at core/nginx/conf/proxy.conf hid the header from upstream responses but did not overwrite the incoming request value in this configuration. An unauthenticated remote attacker could therefore spoof the trusted proxy identity and bypass authentication. This issue is fixed in Mailu 2024.06.55 and Mailu helm-charts 2.7.3.
Impact#
Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.
Weaknesses#
References#
- https://github.com/Mailu/Mailu/security/advisories/GHSA-rfhj-4wcq-74xg
- https://github.com/Mailu/Mailu/pull/4070
- https://github.com/Mailu/Mailu/pull/4071
- https://github.com/Mailu/Mailu/commit/dffa97cbd889ab208246372ce9c86e99abb27ae9
- https://github.com/Mailu/Mailu/commit/ff4003d045753013470945336448dbd790cac778
- https://github.com/Mailu/Mailu/releases/tag/2024.06.55
Exploit#
No public exploit known
History#
- Version 1Record published in the CVE List.