Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting') (CWE-113)

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

The product receives data from an HTTP agent/component, and it places this data in HTTP response headers without neutralizing CRLF sequences.

An attacker can inject CRLF sequences into HTTP headers to create additional headers or response body content. This can lead to cache poisoning, cross-site scripting, or other attacks.

Prevalência

Média

3 linguagens cobertas

Impacto

Alto

2 regras de severidade alta

Prevenção

Documentada

3 exemplos de correção

2 Prevenção

Como corrigir esta vulnerabilidade

Estratégias de prevenção para HTTP Response Splitting baseadas em 3 regras de detecção do Shoulder.

🐹 Go Ver tudo Go detalhes →

HTTP Header Injection MEDIUM

Strip CRLF characters from user input before setting HTTP headers

+15 -6 go

  package main
  
- import "net/http"
- 
- func handler(w http.ResponseWriter, r *http.Request) {
-     lang := r.URL.Query().Get("lang")
-     // Vulnerable: user input set as header value
-     w.Header().Set("Content-Language", lang)
+ import (
+     "net/http"
+     "strings"
+ )
+ 
+ func sanitizeHeaderValue(s string) string {
+     s = strings.ReplaceAll(s, "\r", "")
+     s = strings.ReplaceAll(s, "\n", "")
+     return s
+ }
+ 
+ func handler(w http.ResponseWriter, r *http.Request) {
+     lang := r.URL.Query().Get("lang")
+     // Safe: CRLF characters stripped
+     w.Header().Set("Content-Language", sanitizeHeaderValue(lang))
      w.Write([]byte("OK"))
  }

🐍 Python Ver tudo Python detalhes →

HTTP Header Injection HIGH

Strip CRLF characters from user input before using in HTTP headers

+12 -7 python

- from flask import request, make_response
- 
- @app.route('/download')
- def download():
-     filename = request.args.get('filename')
-     response = make_response("content")
-     response.headers['Content-Disposition'] = f'attachment; filename="{filename}"'
+ import re
+ from flask import request, make_response
+ 
+ def sanitize_header(value):
+     return re.sub(r'[\r\n]', '', str(value))
+ 
+ @app.route('/download')
+ def download():
+     filename = request.args.get('filename', '')
+     safe_filename = sanitize_header(filename)
+     response = make_response("content")
+     response.headers['Content-Disposition'] = f'attachment; filename="{safe_filename}"'
      return response

3 Detecção

Encontre vulnerabilidades no seu código

Use o Shoulder para escanear seu código em busca de padrões Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting'). 3 regras.

terminal

# Scan with Shoulder CLI
npx @shoulderdev/cli trust --cwe=113

# Or scan entire project
npx @shoulderdev/cli trust .

Regras de Detecção (3)

🐹 Go 1 rules

HTTP Header Injection MEDIUM

Detects user input flowing to HTTP headers without CRLF sanitization.

🟨 Javascript 1 rules

HTTP Header Injection (Response Splitting) HIGH

Detects user input flowing into HTTP response headers without CRLF sanitization.

🔷 Typescript 1 rules

HTTP Header Injection (Response Splitting) HIGH

Detects user input flowing into HTTP response headers without CRLF sanitization.

🐍 Python 1 rules

HTTP Header Injection HIGH

Detects user input flowing into HTTP response headers without CRLF sanitization.

4 Sinais de Alerta

O que observar nas revisões de código

Estes padrões indicam vulnerabilidades potenciais de Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting'). Procure-os durante revisões de código e auditorias de segurança.

🟠

user input flowing into HTTP response headers without CRLF sanitization javascript-header-injection

🟡

user input flowing to HTTP headers without CRLF sanitization go-header-injection

🔍

Escaneie seu código para Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

O Shoulder CLI encontra padrões vulneráveis em todo o seu código.

npx shoulder trust Ver todas as regras