GHSA-gwfg-cqmg-cf8f WEBRick vulnerable to HTTP Request/Response Smuggling

• RubyGems webrick: >= 1.6.0, < 1.6.1 → fixed in 1.6.1 • RubyGems webrick: >= 1.5.0, < 1.5.1 → fixed in 1.5.1 • RubyGems webrick: < 1.4.4 → fixed in 1.4.4

An issue was discovered in Ruby through 2.5.8, 2.6.x through 2.6.6, and 2.7.x through 2.7.1. WEBrick, a simple HTTP server bundled with Ruby, had not checked the transfer-encoding header value rigorously. An attacker may potentially exploit this issue to bypass a reverse proxy (which also has a poor header check), which may lead to an HTTP Request Smuggling attack.