CVE-2026-85751: falha crítica em Mailu
Mailu: Authentication bypass in header-based proxy authentication via spoofable `X-Forwarded-By` trust
Publicada em
Aviso por e-mail quando ela entrar no KEV, ganhar PoC pública ou subir de nota.
28Vexday Risk Score
Sem sinal de exploração. Nenhum artefato público de exploração conhecido até agora.
ssvc Trackcvss 9.8epss 0.6%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVEs relacionadas — Mailu
No mesmo produto, das mais perigosas para as menos.
CVE-2020-5239HIGHUnspecified vulnerability in the fetchmail script in MailuEPSS 0.9%CVE-2026-86009HIGHMailu: Domain managers can allow themselves to spoof on other hosted domains they should not controlEPSS 0.4%CVE-2026-49217HIGHMailu missing authentication on PATCH /api/v1/token/<id>, which allows unauthenticated removal of IP restrictionsEPSS 0.4%CVE-2026-86008HIGHMailu domain managers can take over higher-privileged accountsEPSS 0.3%
Referências
https://github.com/Mailu/Mailu/commit/dffa97cbd889ab208246372ce9c86e99abb27ae9https://github.com/Mailu/Mailu/commit/ff4003d045753013470945336448dbd790cac778https://github.com/Mailu/Mailu/pull/4070https://github.com/Mailu/Mailu/pull/4071https://github.com/Mailu/Mailu/releases/tag/2024.06.55https://github.com/Mailu/Mailu/security/advisories/GHSA-rfhj-4wcq-74xg