Python-Hyper H2 vulnerabilities

CVE-2025-57804 [MEDIUM] CWE-93 CVE-2025-57804: h2 is a pure-Python implementation of a HTTP/2 protocol stack. Prior to version 4.3.0, an HTTP/2 req h2 is a pure-Python implementation of a HTTP/2 protocol stack. Prior to version 4.3.0, an HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attac

CVE-2026-71554 [MEDIUM] CWE-444 CVE-2026-71554: h2 is a pure-Python implementation of a HTTP/2 protocol stack. Versions up to and including 4.4.0 ac h2 is a pure-Python implementation of a HTTP/2 protocol stack. Versions up to and including 4.4.0 accept request header blocks containing more than one Host header, and forward every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request carries two Host header lines, providing a request smu