Improper Output Neutralization for Logs
The product does not neutralize or incorrectly neutralizes output that is written to logs.
Log injection attacks occur when user input is written to log files without proper sanitization. This can allow attackers to forge log entries, inject malicious content, or exploit log analysis tools.
Comment corriger cette vulnérabilité
Stratégies de prévention pour Log Injection basées sur 4 règles de détection Shoulder.
Strip newlines and control characters from user input before logging
package main import ( "log" "net/http" - ) - - func handler(w http.ResponseWriter, r *http.Request) { - username := r.URL.Query().Get("user") - // Vulnerable: user input logged directly - log.Printf("Login attempt for user: %s", username) + "strings" + ) + + func sanitizeLogInput(s string) string { + s = strings.ReplaceAll(s, "\n", "") + s = strings.ReplaceAll(s, "\r", "") + return s + } + + func handler(w http.ResponseWriter, r *http.Request) { + username := r.URL.Query().Get("user") + // Safe: newlines stripped before logging + log.Printf("Login attempt for user: %s", sanitizeLogInput(username)) }
Strip newline characters from user input before writing to log files
const express = require('express'); const winston = require('winston'); const app = express(); app.post('/login', (req, res) => { - const username = req.body.username; + const username = req.body.username.replace(/[\r\n]/g, ''); winston.info(`Login attempt: ${username}`); res.json({ status: 'ok' }); });
Sanitize user input by stripping CRLF characters before writing to logs
- app.post('/login', (req, res) => { - logger.info(`Login attempt from: ${req.body.username}`); + const sanitize = (str) => str.replace(/[\r\n]/g, '').substring(0, 200); + + app.post('/login', (req, res) => { + logger.info('Login attempt', { username: sanitize(req.body.username) }); });
Use structured logging with separate fields for user data instead of string interpolation
import logging from flask import request - @app.route('/login', methods=['POST']) - def login(): - username = request.form.get('username') - logging.info(f"Login attempt for user: {username}") + logger = logging.getLogger(__name__) + + @app.route('/login', methods=['POST']) + def login(): + username = request.form.get('username', '') + logger.info("Login attempt", extra={'username': username}) return "OK"
Trouvez les vulnérabilités dans votre code
Utilisez Shoulder pour scanner votre code à la recherche de patterns Improper Output Neutralization for Logs. 4 règles.
# Scan with Shoulder CLI npx @shoulderdev/cli trust --cwe=117 # Or scan entire project npx @shoulderdev/cli trust .
Règles de Détection (4)
Ce qu'il faut surveiller lors des revues de code
Ces patterns indiquent des vulnérabilités potentielles Improper Output Neutralization for Logs. Recherchez-les lors des revues de code et des audits de sécurité.
Scannez votre base de code pour Improper Output Neutralization for Logs
Shoulder CLI trouve les motifs vulnérables dans toute votre base de code.