seclab/MOD6_Incident_Response.md

# FILE: MOD6_Incident_Response.md
# MODULE 6: INCIDENT RESPONSE & DIGITAL FORENSICS

## Learning Objectives
- Follow NIST Incident Response lifecycle (PICERL)
- Acquire forensic disk and memory images
- Analyze artifacts with Autopsy and Volatility
- Reconstruct attack timelines from logs and forensics
- Write comprehensive incident response reports

---

## NIST IR LIFECYCLE

**PICERL Framework:**
1. **Preparation:** Tools, procedures, training
2. **Identification:** Detect and validate incidents
3. **Containment:** Limit damage (short-term & long-term)
4. **Eradication:** Remove threat from environment
5. **Recovery:** Restore systems to normal operation
6. **Lessons Learned:** Post-incident review

---

## LAB 6.1: DISK FORENSICS WITH AUTOPSY

### Acquire Disk Image

```bash
# On Proxmox, snapshot compromised Metasploitable VM
qm snapshot 401 forensics-image --description "Post-compromise forensic capture"

# Export disk image
qm stop 401
dd if=/dev/pve/vm-401-disk-0 of=/root/metasploitable_forensics.dd bs=4M
# Or use FTK Imager on Windows for E01 format

# Calculate hash (evidence integrity)
md5sum /root/metasploitable_forensics.dd > metasploitable.md5
sha256sum /root/metasploitable_forensics.dd > metasploitable.sha256
```

### Analyze with Autopsy

```
1. Install Autopsy (on analyst workstation or Kali):
   sudo apt install autopsy

2. Start Autopsy:
   autopsy
   # Opens browser to http://localhost:9999/autopsy

3. Create New Case:
   - Case Name: Metasploitable Compromise Investigation
   - Description: Analysis of MOD3 exploitation artifacts
   - Investigator: [Your Name]

4. Add Data Source:
   - Type: Disk Image
   - Path: /root/metasploitable_forensics.dd
   - Import method: Calculate hash
   - Ingest modules: Select all

5. Key Analysis Areas:

   TIMELINE ANALYSIS:
   - Tools > Generate Timeline
   - Filter by date of compromise
   - Look for: File modifications, command execution, new processes

   WEB ARTIFACTS:
   - Data Artifacts > Web History
   - Check for attacker tool downloads

   FILE ANALYSIS:
   - Deleted Files > Recover
   - Look in /tmp, /var/tmp for attacker tools
   - Search for .bash_history files

   KEYWORD SEARCH:
   - Search: "backdoor", "shell", "exploit"
   - Search IPs: 10.10.2.50 (Kali attacker)

   HASH ANALYSIS:
   - File > Hash Lookup
   - Compare against NSRL (known good files)
   - Identify unknown binaries (potential malware)
```

### Key IOCs to Document
- New user accounts created
- Modified /etc/passwd, /etc/shadow
- Suspicious cron jobs
- Backdoor files in /tmp, /var/www
- SSH authorized_keys modifications
- Large outbound network transfers

---

## LAB 6.2: MEMORY FORENSICS WITH VOLATILITY

### Capture Memory Dump

```bash
# From Proxmox, capture running VM memory
virsh dump 401 /root/metasploitable_memory.dump --memory-only

# Or use LiME (Linux Memory Extractor) from within VM
git clone https://github.com/504ensicsLabs/LiME
cd LiME/src
make
sudo insmod lime-$(uname -r).ko "path=/tmp/memory.lime format=lime"
```

### Analyze with Volatility 3

```bash
# Install Volatility 3
git clone https://github.com/volatilityfoundation/volatility3
cd volatility3
python3 setup.py install

# Identify OS profile
vol -f /root/metasploitable_memory.dump banners.Banners

# List processes
vol -f /root/metasploitable_memory.dump linux.pslist.PsList

# Find suspicious processes (look for bash, nc, python shells)
vol -f /root/metasploitable_memory.dump linux.pslist.PsList | grep -E "bash|nc|python"

# View command line arguments
vol -f /root/metasploitable_memory.dump linux.cmdline.CmdLine

# Network connections
vol -f /root/metasploitable_memory.dump linux.netstat.Netstat
# Look for connections to 10.10.2.50:4444 (reverse shell)

# Extract process memory
vol -f /root/metasploitable_memory.dump -o /tmp/dump linux.proc.Maps --pid 1234 --dump

# Bash history from memory
vol -f /root/metasploitable_memory.dump linux.bash.Bash

# Loaded kernel modules (rootkit detection)
vol -f /root/metasploitable_memory.dump linux.lsmod.Lsmod
```

---

## LAB 6.3: NETWORK FORENSICS

### PCAP Analysis from MOD3 Exploitation

```bash
# Analyze saved packet capture from Wireshark

# Extract files transferred over HTTP
tcpflow -r exploit_traffic.pcap -o extracted_files/

# Reconstruct TCP streams
for stream in $(tshark -r exploit_traffic.pcap -T fields -e tcp.stream | sort -u); do
    tshark -r exploit_traffic.pcap -q -z follow,tcp,ascii,$stream
done

# Find reverse shell traffic
tshark -r exploit_traffic.pcap -Y "tcp.dstport == 4444" -T fields -e frame.time -e ip.src -e ip.dst -e tcp.payload

# DNS exfiltration detection (long domain names)
tshark -r exploit_traffic.pcap -Y "dns.qry.name.len > 50" -T fields -e dns.qry.name
```

### Using NetworkMiner (GUI alternative)

```
1. Install NetworkMiner (Windows or Linux)
2. Open exploit_traffic.pcap
3. View tabs:
   - Hosts: See attacker (10.10.2.50) and victim (10.10.4.10)
   - Files: Auto-extracted files transferred
   - Credentials: Captured plaintext passwords
   - Sessions: TCP conversations
   - DNS: Domain lookups
```

---

## LAB 6.4: LOG ANALYSIS FOR IR

### Linux System Log Analysis

```bash
# Authentication logs
sudo grep "Failed password" /var/log/auth.log | wc -l
# Count brute-force attempts

# Successful logins after failures
sudo grep "Accepted password" /var/log/auth.log | tail -n 20

# New user creation
sudo grep "useradd" /var/log/auth.log

# Sudo command execution
sudo grep "COMMAND" /var/log/auth.log

# Cron job modifications
sudo grep "cron" /var/log/syslog

# Web server access logs
tail -n 100 /var/log/apache2/access.log
# Look for exploit payloads in URLs
grep -E "\.\.\/|<script|UNION|cmd=" /var/log/apache2/access.log
```

### Timeline Creation

```bash
# Combine all logs by timestamp
cat /var/log/auth.log /var/log/syslog /var/log/apache2/access.log | sort -k1,3 > combined_timeline.txt

# Or use log2timeline (Plaso)
log2timeline.py --storage_file timeline.plaso /var/log/
psort.py -o l2tcsv -w timeline.csv timeline.plaso
```

---

## LAB 6.5: INCIDENT REPORT WRITING

### Report Structure

```markdown
# INCIDENT RESPONSE REPORT
**Case ID:** IR-2026-02-001
**Incident Type:** Unauthorized Access - Exploitation
**Severity:** CRITICAL
**Status:** Contained
**Date Range:** 2026-02-11 14:00 - 15:30 UTC
**Analyst:** [Your Name]

## EXECUTIVE SUMMARY
On February 11, 2026, at approximately 14:00 UTC, an unauthorized actor exploited a vulnerable FTP service (vsftpd 2.3.4) on production server 10.10.4.10, gaining root-level access. The attacker performed credential harvesting and established persistence via SSH key injection. The incident was contained at 15:30 UTC with no evidence of data exfiltration.

## TIMELINE OF EVENTS
| Time (UTC) | Event | Source |
|------------|-------|--------|
| 14:00:15 | Port scan detected from 10.10.2.50 | Suricata IDS |
| 14:15:32 | vsftpd backdoor triggered | auth.log |
| 14:16:05 | Root shell established on port 6200 | netstat, PCAP |
| 14:18:22 | /etc/shadow downloaded | File integrity monitoring |
| 14:20:45 | SSH authorized_keys modified | auth.log |
| 14:25:10 | Incident detected by SOC analyst | Security Onion alert |
| 15:30:00 | Server isolated, attacker access terminated | Firewall logs |

## INDICATORS OF COMPROMISE (IOCs)
**Network:**
- Attacker IP: 10.10.2.50
- C2 Port: 6200 (vsftpd backdoor)
- Reverse shell: 10.10.2.50:4444

**File System:**
- /root/.ssh/authorized_keys (modified 2026-02-11 14:20:45)
- /tmp/.hidden_shell.sh (created 2026-02-11 14:17:00)
- MD5: a3f5b8c9e2d1f4a6b7c8d9e0f1a2b3c4

**Processes:**
- PID 6543: /bin/bash (spawned by vsftpd, uid=0)

## ROOT CAUSE ANALYSIS
1. **Vulnerability:** vsftpd 2.3.4 contains hardcoded backdoor (CVE-2011-2523)
2. **Lack of Patching:** Service running outdated version (released 2011)
3. **Detection Gap:** IDS signature existed but alert was not tuned for priority response
4. **Network Segmentation Failure:** Victim server allowed outbound connection to attacker network

## CONTAINMENT ACTIONS
1. Isolated server at network layer (pfSense block rule)
2. Terminated attacker SSH sessions (killed PIDs)
3. Disabled vsftpd service (systemctl stop vsftpd)
4. Changed all system passwords
5. Removed unauthorized SSH keys

## ERADICATION
1. Rebuilt server from clean snapshot (pre-compromise)
2. Patched vsftpd to version 3.0.5
3. Removed attacker-created user accounts
4. Cleared cron jobs

## RECOVERY
1. Validated system integrity (rkhunter, chkrootkit)
2. Restored from secure backup
3. Monitored for 48 hours (no reinfection)
4. Returned to production 2026-02-13 10:00 UTC

## LESSONS LEARNED
**What Went Well:**
- IDS detected reconnaissance phase
- Forensic artifacts preserved due to snapshot policy
- Incident contained within 90 minutes of detection

**What Needs Improvement:**
- Vulnerability management process (vsftpd was 15 years old!)
- Alert prioritization (scan alerts should trigger immediate investigation)
- Egress filtering (victim should not reach Red Team network)

## RECOMMENDATIONS
1. **Immediate:** Implement vulnerability scanning (weekly, automated)
2. **Short-term:** Deploy application whitelisting on critical servers
3. **Long-term:** Implement zero-trust architecture (segment victim networks further)
4. **Process:** Conduct tabletop exercises quarterly

## APPENDICES
- Appendix A: Full network packet capture (exploit_traffic.pcapng)
- Appendix B: Disk forensic image hash (SHA256: abc123...)
- Appendix C: Memory dump analysis (Volatility output)
- Appendix D: Log files (auth.log, syslog, apache2 access.log)
```

---

## KNOWLEDGE CHECK

1. **What are the 6 phases of NIST incident response?**
   - Answer: Preparation, Identification, Containment, Eradication, Recovery, Lessons Learned

2. **Why must forensic images be hashed?**
   - Answer: Prove integrity and chain of custody for legal admissibility

3. **What Volatility command lists running processes?**
   - Answer: `linux.pslist.PsList` (or `windows.pslist` for Windows)

4. **Name 3 IOCs from the example incident**
   - Answer: Attacker IP 10.10.2.50, modified authorized_keys, vsftpd backdoor port 6200

---

## DELIVERABLES

- [ ] Disk forensic image with hash values
- [ ] Memory dump with Volatility analysis report
- [ ] PCAP file from exploitation phase
- [ ] Complete incident timeline (spreadsheet)
- [ ] Full incident response report (10+ pages)
- [ ] Lessons learned presentation

---

**END OF MODULE 6**

Proceed to **MOD7: Web Application Security** to expand attack surface knowledge.