CVE-2026-43972 gun HTTP/2 PUSH_PROMISE authority not validated against connection origin allows cross-origin cookie injection

Origin Validation Error vulnerability in ninenines gun gunhttp2 module allows cross-origin cookie injection via unvalidated HTTP/2 PUSHPROMISE authority. In gunhttp2:pushpromiseframe/7, the :authority pseudo-header from an incoming PUSHPROMISE frame is stored verbatim into the promised stream...