CVE-2026-105299 Evasión de ACL en Pingora por reenvío de encabezados Connection a upstreams HTTP/1

Qué es CVE-2026-105299

Antes de la versión 0.9.0, la ruta de upstream HTTP/1 de pingora-proxy reenviaba la solicitud sin eliminar el encabezado Connection del cliente, otros encabezados hop-by-hop ni los encabezados nominados por Connection. Un cliente podría nominar un encabezado que la aplicación agrega en upstream_request_filter, y un intermediario HTTP/1 que respete Connection lo eliminaría antes de llegar al origen. Afecta específicamente a despliegues encadenados con un intermediario HTTP/1 entre Pingora y el origen.

Productos y versiones afectadas

• Cloudflare https://github.com/cloudflare/pingora

  • desde 0.1.0 hasta antes de 0.9.0

Qué hacer

1. Verificá si usás https://github.com/cloudflare/pingora y en qué versión: el rango afectado figura arriba.
2. Actualizá a la versión corregida que indique el fabricante en su aviso (ver referencias) o aplicá la mitigación que publique.
3. Revisá registros y accesos de los sistemas expuestos para descartar que se haya aprovechado antes de corregir.

Calculadora CVSS

CVSS 3.1 · 8.7 ALTA

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

VECTOR DE ATAQUE (AV)

Red

COMPLEJIDAD DEL ATAQUE (AC)

Alta

PRIVILEGIOS REQUERIDOS (PR)

Ninguno

INTERACCIÓN DEL USUARIO (UI)

Ninguna

ALCANCE (S)

Cambiado

CONFIDENCIALIDAD (C)

Alta

INTEGRIDAD (I)

Alta

DISPONIBILIDAD (A)

Ninguna

Abrir la calculadora completa →

Descripción original

Summary Before version 0.9.0, the HTTP/1 upstream path in pingora-proxy passed the downstream request through upstream_request_filter and wrote it to the upstream without removing the client's Connection header, other hop-by-hop headers, or the headers Connection nominated, although RFC 9110 Section 7.6.1 requires intermediaries to remove them. The HTTP/2 upstream path already removed Connection and related HTTP/1-specific headers. A client could therefore nominate a header that the application adds in upstream_request_filter (for example, Connection: keep-alive, X-Forwarded-For). A downstream HTTP/1 intermediary that honors Connection would then strip the Pingora-added header before it reached the origin. Impact Specifically affects chained deployments where an HTTP/1 intermediary between Pingora and the origin processes Connection nominations (for example, Go's net/http/httputil.ReverseProxy) and the origin trusts headers added by that intermediary (for example, X-Forwarded-For for IP-based authorization). A remote, unauthenticated attacker can have those headers removed, potentially bypassing authorization. The reporter demonstrated access to an IP-restricted endpoint using X-Forwarded-For for IP validation on the origin. This is the same class of issue as CVE-2022-31813 in Apache HTTP Server. Note that Cloudflare CDN customers were unaffected, as no such chained deployment as described above exists with internal Pingora services, and Connection headers are sanitized before arriving at Pingora gateways. Mitigation: * Upgrade to pingora 0.9.0 or later. By default, Pingora now removes hop-by-hop and Connection-nominated headers from upstream requests, and rejects requests whose Connection header nominates Host, X-Forwarded-For, X-Forwarded-Host, X-Forwarded-Proto, or a pseudo-header. This is controlled by PeerOptions::http_upstream_request_policy (HttpUpstreamRequestPolicy). Fix commits: https://github.com/cloudflare/pingora/commit/28c18e6b6b04dd0bd937234e5950049e6d74cded , https://github.com/cloudflare/pingora/commit/ca23f1668eca8e78be7ba62ef0edbd458b40eeee * Do not use HttpUpstreamRequestPolicy::preserve() if the origin relies on headers added by Pingora; it restores the old passthrough behavior. * If you cannot upgrade: in upstream_request_filter, remove the Connection header and every header it nominates before adding trusted headers.

Referencias

• github.com/cloudflare/pingora

Historial de la alerta

1. 20 OCT · 00:17VULNERABILIDAD Nueva vulnerabilidad detectada.

CÓMO SE HIZOResumen traducido automáticamente al español a partir de la descripción original. Ante dudas, la descripción original y las referencias del fabricante son la fuente de verdad. Cómo funciona.