Table of Contents
Ch 4: Environmental Setup and Traffic Interception
Source: Bug Bounty Bootcamp by Vickie Li (No Starch Press, 2021)
OS
Use a Unix-based system. Kali Linux is recommended – it ships with Burp Suite, Gobuster, DirBuster, Wfuzz, and other tools. macOS also works fine.
Burp Suite
Burp is a web proxy that sits between your browser and the server, intercepting and allowing modification of every HTTP/HTTPS request and response.
- Community – free; intruder is rate-limited; no scanner; no session saving
- Professional – paid; full intruder speed; active scanner; session saving; match-and-replace rules
Firefox + Burp Setup
- Open Firefox > Preferences > General > Network Settings
- Select Manual proxy configuration
- HTTP Proxy: `127.0.0.1`, Port: `8080`, check “Also use this proxy for HTTPS”
Install Burp's CA Cert
Required to intercept HTTPS without certificate errors:
- With Burp running, browse to `http://burp/` in Firefox
- Download CA Certificate (top-right link)
- Firefox > Preferences > Privacy & Security > View Certificates > Authorities > Import
- Select the file, check “Trust this CA to identify websites”
- Restart Firefox
Enable Intercept
Burp > Proxy > Intercept > click until it reads Intercept is on. Browse to any HTTPS site to confirm requests appear.
Burp Tools
Proxy – captures all requests/responses. Modify before forwarding. Right-click to send to any other module.
Intruder – automated payload injection. Use for: brute-forcing passwords, iterating IDs for IDOR, fuzzing parameters.
- Send to Intruder > Positions tab: highlight value, click Add
- Payloads tab: paste list
- Start attack, sort results by status/length
Repeater – manually replay and modify individual requests. Most-used for exploitation and bypass testing. Right-click any request > Send to Repeater.
Decoder – encode/decode base64, URL, HTML, hex. Use “Smart decode” when unsure of encoding.
Comparer – diff two requests or responses side by side. Useful for comparing auth vs. unauth responses.
Copy as curl – right-click any request > Copy as curl command. Paste into a report as PoC.
Taking Notes
Organized notes are how you avoid repeating work and missing chains:
- Per-target folder – subfolders per feature (auth, uploads, API, payments)
- Record every weird behavior even if not immediately exploitable – revisit during chaining
- For each vuln class you study: theory, impact, steps to exploit, sample PoC code
- Tools: Obsidian (Markdown + graph view), Sublime Text, XMind for mind maps
- Back up to external drive or cloud regularly
