Parse Apache and Nginx access logs to detect SQL injection attempts, local file inclusion, directory traversal, web scanner fingerprints, and brute-force patterns. Uses regex-based pattern matching against OWASP attack signatures, GeoIP enrichment for source attribution, and statistical anomaly detection for request frequency and response size outliers.
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---
name: analyzing-web-server-logs-for-intrusion
description: >-
Parse Apache and Nginx access logs to detect SQL injection attempts, local file inclusion,
directory traversal, web scanner fingerprints, and brute-force patterns. Uses regex-based
pattern matching against OWASP attack signatures, GeoIP enrichment for source attribution,
and statistical anomaly detection for request frequency and response size outliers.
domain: cybersecurity
subdomain: security-operations
tags: [analyzing, web, server, logs]
version: "1.0"
author: mahipal
license: Apache-2.0
---
# Analyzing Web Server Logs for Intrusion
## When to Use
- When investigating security incidents that require analyzing web server logs for intrusion
- When building detection rules or threat hunting queries for this domain
- When SOC analysts need structured procedures for this analysis type
- When validating security monitoring coverage for related attack techniques
## Prerequisites
- Familiarity with security operations concepts and tools
- Access to a test or lab environment for safe execution
- Python 3.8+ with required dependencies installed
- Appropriate authorization for any testing activities
## Instructions
1. Install dependencies: `pip install geoip2 user-agents`
2. Collect web server access logs in Combined Log Format (Apache) or Nginx default format.
3. Parse each log entry extracting: IP, timestamp, method, URI, status code, response size, user-agent, referer.
4. Apply detection rules:
- SQL injection: `UNION SELECT`, `OR 1=1`, `' OR '`, hex encoding patterns
- LFI/Path traversal: `../`, `/etc/passwd`, `/proc/self`, `php://filter`
- XSS: `<script>`, `javascript:`, `onerror=`, `onload=`
- Scanner signatures: nikto, sqlmap, dirbuster, gobuster, wfuzz user-agents
- Brute force: >50 POST requests to login endpoints from same IP in 5 minutes
5. Enrich with GeoIP data and generate a prioritized findings report.
```bash
python scripts/agent.py --log-file /var/log/nginx/access.log --geoip-db GeoLite2-City.mmdb --output web_intrusion_report.json
```
## Examples
### Detect SQLi in URI
```
192.168.1.100 - - [15/Jan/2024:10:30:45 +0000] "GET /products?id=1' UNION SELECT username,password FROM users-- HTTP/1.1" 200 4532
```
### Scanner User-Agent Detection
```
Nikto/2.1.6, sqlmap/1.7, DirBuster-1.0-RC1, gobuster/3.1.0
```
