Apache Httpd 2.4.18 Exploit May 2026

Apache 2.4.18 failed to properly sanitize user-supplied input in certain rewrite rules or headers. By injecting %0d%0a (CRLF), an attacker could manipulate HTTP response headers.

CVE-2017-9798, discovered by Hanno Böck, was a use-after-free vulnerability in mod_http2 . When Apache 2.4.18 was compiled with HTTP/2 support (not default in 2.4.18, but common), an attacker could trigger a memory leak. The leak disclosed the contents of the server’s memory, potentially including htaccess directives, private keys, or session data. apache httpd 2.4.18 exploit

CVE-2016-5387, nicknamed "HTTPOXY," is a misnomer. It is not an Apache bug per se, but a design flaw in how CGI scripts handled the Proxy header. An attacker could send a request containing a Proxy: http://evil.com header, tricking server-side scripts (PHP, Python, Go) into routing outgoing HTTP requests through a malicious proxy. Apache 2

http://target.com/login?next=/%0d%0aSet-Cookie:%20session=hijacked If the server responded with a Location: /next header containing the unsanitized value, the attacker could inject a second header. When Apache 2

A viable information disclosure tool, but not a remote shell exploit . Searches for an "apache 2.4.18 shell exploit" due to HTTPOXY are misguided. 2. CVE-2016-4975: CRLF Injection & HTTP Response Splitting Severity: 6.1 (Medium) Type: CRLF Injection