CVE-2026-33805criticalCWE-444CWE-644

CVE-2026-33805: fallo crítico en @fastify/reply-from

@fastify/reply-from vulnerable to connection header abuse enabling stripping of proxy-added headers

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear @fastify/reply-from+ Monitorear @fastify/http-proxy

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

28Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 9epss 0.4%
@fastify/reply-from v12.6.1 and earlier and @fastify/http-proxy v11.4.3 and earlier process the client's Connection header after the proxy has added its own headers via rewriteRequestHeaders. This allows attackers to retroactively strip proxy-added headers from upstream requests by listing them in the Connection header value. Any header added by the proxy for routing, access control, or security purposes can be selectively removed by a client. @fastify/http-proxy is also affected as it delegates to @fastify/reply-from. Upgrade to @fastify/reply-from v12.6.2 or @fastify/http-proxy v11.4.4 or later.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/SA:N
Productos afectados
@fastify/reply-from · @fastify/http-proxy@fastify/reply-from · @fastify/reply-from
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