HTTP header injection

HTTP header injection is a general class of web application security vulnerability which occurs when Hypertext Transfer Protocol (HTTP) headers are dynamically generated based on user input. Header injection in HTTP responses can allow for HTTP response splitting, session fixation via the Set-Cookie header, cross-site scripting (XSS), and malicious redirect attacks via the location header. HTTP header injection is a relatively new area for web-based attacks, and has primarily been pioneered by Amit Klein in his work on request/response smuggling/splitting.[1]

HTTP
Persistence Compression HTTPS QUIC
Request methods
OPTIONS GET HEAD POST PUT DELETE TRACE CONNECT PATCH
Header fields
Cookie ETag Location HTTP referer DNT X-Forwarded-For
Response status codes
301 Moved Permanently 302 Found 303 See Other 403 Forbidden 404 Not Found 451 Unavailable for Legal Reasons
Security access control methods
Basic access authentication Digest access authentication
Security vulnerabilities
HTTP header injection HTTP request smuggling HTTP response splitting HTTP parameter pollution