cve-2026-58055

The cve-2026-58055 tag covers security information about a newly disclosed vulnerability in nghttp2’s nghttpx proxy. The issue affects versions through 1.69.0 and can enable HTTP request or response smuggling when an Upgrade request containing Content-Length is forwarded to reusable backend connections. This archive is relevant to administrators running nghttpx as a reverse proxy, gateway, or protocol translation layer. Coverage focuses on the boundary between proxy and backend interpretation, the potential for Content-Length desynchronization, the practical meaning of the medium-severity rating, and the importance of upgrading affected deployments.