CVE-2026-38969: Ruby Webrick Chunked Trailer Injection

WEBrick indiscriminately appends HTTP chunked trailers to the raw request headers buffer and parses them in conjunction with the primary request headers using HTTPUtils::parse_header. This bypasses the trailer/header boundary and allows trailers to overwrite authoritative headers like Content-Length or Host, enabling HTTP Request Smuggling. The patch cleanly

Provally CuratedPublic repositoryHighMedium confidenceVerifiedApache-2.0Ruby
greprules fetch cve-2026-38969-ruby-webrick-chunked-trailer-injection --engine opengrep

Description

WEBrick indiscriminately appends HTTP chunked trailers to the raw request headers buffer and parses them in conjunction with the primary request headers using HTTPUtils::parse_header. This bypasses the trailer/header boundary and allows trailers to overwrite authoritative headers like Content-Length or Host, enabling HTTP Request Smuggling. The patch cleanly