Apache HTTP Server 2.4.53 and earlier may not send the X-Forwarded-* headers to the origin server based on client side Connection header hop-by-hop mechanism. This may be used to bypass IP based authentication on the origin server/application.
{ "cpes": [ "cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*" ], "severity": "Critical" }