Vulnerabilidad · Publicado 21/08/2026
El proxy LLM de Headroom contiene una vulnerabilidad de redirección abierta que permite a clientes no autenticados especificar destinos upstream arbitrarios mediante el encabezado x-headroom-base-url. Un atacante puede redirigir solicitudes de LLM hacia servidores maliciosos bajo su control para interceptar datos sensibles, credenciales de API o prompts confidenciales. Afecta directamente a empresas en LATAM que implementan soluciones de proxy centralizado para modelos de lenguaje en arquitecturas de integración con proveedores cloud.
Headroom's LLM proxy lets a client choose the upstream destination with the x-headroom-base-url request header. _resolve_openai_upstream_base in headroom/proxy/handlers/openai.py accepts the header value, requires only that it parse with an http or https scheme and a hostname, and returns it for use as the upstream base; _select_passthrough_base_url in headroom/providers/proxy_routes.py reads the same header for the passthrough routes. No check rejects loopback, link-local, or RFC 1918 destinations, and because the component is a proxy the upstream response is returned to the caller, so the request reaches internal services and cloud metadata addresses and their responses are disclosed. The Authorization header accompanying the request is forwarded unchanged to the caller-designated host. The pip console script binds 127.0.0.1 by default, but the reference docker-compose.yml ships --host 0.0.0.0 with published ports and no required HEADROOM_PROXY_TOKEN, which the server itself warns about at startup, so a deployment following the shipped compose exposes the affected data-plane routes to the network without authentication.
Score: 8.6/10 — Severidad: HIGH — Estado NIST: Received
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
CWE-918
Publicado en NIST NVD.