Fuzz Agent Skill

fuzz - adaptive web fuzzing

0. Profile (do this first)

Read engagement_type from the active targets/<eng>/state.md frontmatter and set the profile:

• ctf - loud/fast, ignore WAF, recurse deep, exhaust the big list.
• pt - calibrated rate, obey RoE flags (no_bruteforce/no_dos -> SKIP the brute tiers entirely).
• bb - stealth: low rate + jitter, watch for the ban BEFORE it lands, request-budget aware.

wl-pick.sh emits the profile flags; you apply them.

1. Two axes

• Surface (widen): content, files, vhost, api, artifacts. Recursive by default.
• Parameter (deepen): once an endpoint takes input, fuzz hidden params. Triggered by OBSERVING a param-accepting endpoint, never blind.

2. Select (deterministic) - always via wl-pick.sh

# what to run for a surface, given the engagement type and any fingerprint:
bash scripts/wl-pick.sh content "" ctf          # generic content discovery
bash scripts/wl-pick.sh content wordpress bb    # WordPress-aware, BB-stealth
bash scripts/wl-pick.sh vhost "" pt
bash scripts/wl-pick.sh params "" bb

It prints the seclists base, the profile flags line, and the ordered absolute paths (T0 harness -> T3 fingerprint list -> T1 surface lists, size-ordered). NEVER hand-pick a list from memory and NEVER start with directory-list-2.3-medium (220k). The size order is already correct in the output; run top-to-bottom, stop climbing when you have enough signal.

3. Calibrate (native first, backstop with judgment)

• Default to ffuf -ac/-acc and feroxbuster auto-filtering.
• If a wildcard/soft-404 fools -ac (everything returns 200 with varying size): fire 2-3 known-bogus random paths first, read status/size/words, then set explicit -fs/-fw on the catch-all baseline, or -mc 200,301,302,401,403 on a clean 404.
• READ tool output END-TO-END, never a grep. A real hit hides in the noise.

4. Climb tiers on SIGNAL (the adaptive core)

Climb T0 -> T1 -> T2 -> T3 when the current tier is exhausted OR a fingerprint unlocks a better list:

• T2 cewl when T0/T1 run dry: cewl -d 3 -m 5 --lowercase -w targets/<eng>/custom-words.txt https://TARGET then feed that list back through the same axis. See [[cewl]].
• T3 app-specific the moment you fingerprint a known product: re-run wl-pick.sh <surface> <product> <type> to jump straight to its shipped list. For a product with no shipped list, Skill(wiki-arsenal) for its known paths, then cewl its docs / probe robots.txt sitemap.xml swagger.json openapi.json.

5. Pivot to the parameter axis

When a discovered endpoint takes input, fuzz hidden params: arjun -u https://TARGET/endpoint (see [[arjun]]) or ffuf with bash scripts/wl-pick.sh params. Discovered params feed the hunt-* skills (SSRF/LFI/IDOR/cmdi).

6. WAF / throttle / Cloudflare

Detect: wafw00f/whatwaf up front; headers cf-ray/server: cloudflare/x-sucuri/x-datadome/incapsula; mid-run 429+Retry-After, climbing latency, 000/timeouts, a wall of uniform 403.

Respond, in order:

• WAF fingerprinted up front -> stealth posture regardless of profile, and PREFER BYPASS over throttle: find the origin IP (cert SANs, historical DNS) and fuzz origin directly - see [[cdn-waf-bypass]].
• Throttle mid-run -> auto-backoff: halve rate, add -p 0.1-2.0 jitter, drop one size-tier.
• Ban / DoS tell (sustained all-timeout after a burst) -> HARD STOP, do not grind: python3 scripts/campaign.py pause-host <host> and call Skill(redteamlead) for a re-vector rather than tuning the tooling.
• RoE no_bruteforce/no_dos -> skip the brute tiers; scope-guard also enforces this at the Bash layer.

7. 403 is not a dead end

A 403 on a discovered dir is a signal, not an end. Try bypass BEFORE abandoning: path mutations (/admin/, /admin/., /admin/..;/, /%2e/admin, case, trailing ?), method swap (GET->POST/HEAD/TRACE), and header spoofs (X-Forwarded-For: 127.0.0.1, X-Original-URL, X-Rewrite-URL). Use a dedicated tool (byp4xx/nomore403) rather than a wordlist - 403 bypass is mutation, not brute. See [[cdn-waf-bypass]].

Wiki

Tools: [[ffuf]] [[wiki/tools/feroxbuster]] [[cewl]] [[arjun]]. Reference: [[wordlists]] (the selection matrix, human-readable twin of wordlist-map.json), [[cdn-waf-bypass]] (WAF/origin bypass). Stuck -> Skill(redteamlead).