webvuln

Web vuln hunting playbook

You are testing specific endpoints the user has handed you (or that came out of the recon skill). Every finding must come with a real PoC and a concrete impact statement — no theoretical bugs.

Default to curl and the built-in http tool. Do not pull in heavy scanners (nuclei, sqlmap, ffuf, etc.) unless the user explicitly asks for them or you have manually confirmed a bug and need a scanner only to characterize the bug class.

Execution rule: substitute real target values before running commands. Never write literal placeholders such as <TARGET>, <vulnerable-path>, or <PoC body> to files. If a value is unknown, ask once or derive it from /target.

1. Triage the target

Fetch the landing page with the http tool or curl. Note:

• Framework / language signals (cookies, headers, error pages)
• Authentication scheme (cookie, Bearer, basic)
• API style (REST / GraphQL / gRPC)
• Anything that suggests a known CVE family (versioned banner, vendor product name)

If you spot a versioned product, immediately web_search "<product> <version> CVE" and web_fetch the top advisory. Reproduce the CVE manually with curl before reporting.

2. Known-CVE pass (manual, curl-driven)

For each suspected CVE pulled from the advisory, craft the curl that proves it — single request when possible:

TARGET="https://app.example.com" # replace with the scoped target before running
curl -ksS -X POST "$TARGET/vulnerable-path" \
  -H 'Content-Type: application/json' \
  -d '{"replace":"with-real-poc-body"}' \
  -w "\nHTTP %{http_code}  size=%{size_download}  time=%{time_total}\n"

If the advisory describes a recognizable pattern (template injection, deserialization, etc.) and the user has explicitly authorized broader scanning, then — and only then — reach for nuclei against the single host. Otherwise stay manual.

3. Auth + access control (IDOR / BAC)

• Identify any numeric or UUID identifiers in the URL path or query (/api/users/12345, /orders/?id=...).
• With user-provided session A, fetch a resource you own.
• Swap the identifier to another user's value (or use a second session from the user) and replay with curl or the http tool.
• A 200 with foreign data = IDOR. Capture the curl one-liner and the response excerpt into findings/idor-<endpoint>.txt.

Example IDOR sweep with two sessions:

TARGET="https://app.example.com" # replace with the scoped target before running
for id in $(seq 1 50); do
  body=$(curl -ksS -H "Cookie: $SESSION_B" "$TARGET/api/users/$id" | jq -r '.email // empty')
  [ -n "$body" ] && echo "$id $body"
done

4. Injection surfaces (curl-first)

For each parameter (query, body, header, cookie):

• Inject simple probes (', ", <x>, ${7*7}, {{7*7}}) with curl or the http tool.
• 500s / reflected payloads / arithmetic evaluation → escalate to a targeted PoC.

Quick reflected-XSS probe with curl:

TARGET="https://app.example.com" # replace with the scoped target before running
for p in q s search query keyword; do
  curl -ksS "$TARGET/?$p=pf$(date +%s)<svg/onload=alert(1)>" \
    | grep -o "pf[0-9]*<svg.*alert(1)>" || true
done

For SQLi: only after curl-level manual confirmation (timing differences, error strings) and only with the user's explicit OK, escalate to sqlmap with --batch --level=2 --risk=1 --random-agent against the single endpoint. Default path is manual ' OR sleep(5) -- style probes via curl, then exfil via UNION when you know the schema.

5. SSRF & open redirects

Any parameter that takes a URL or hostname: try http://127.0.0.1, http://169.254.169.254/latest/meta-data/, and an out-of-band canary the user provides. Compare response timings and bodies with curl -w "%{time_total} %{size_download}\n".

6. Report

For each confirmed finding, write findings/<id>-<short-title>.md with:

• Title, severity (VRT-aligned), category
• Affected endpoint(s)
• Step-by-step reproduction as the exact curl one-liner the reviewer can copy (with placeholders for session tokens)
• Observed response excerpt proving the bug
• Concrete impact (what data is exposed, what state can be changed, what privilege is escalated)
• Suggested remediation

Stop after writing the report. Do not chain into further exploitation unless the user explicitly asks.