waf-bypass

waf-bypass is a skill for Claude Code from PurpleAILAB/Decepticon. It costs 48 tokens per session (3,846 once invoked), scanned A, original, Apache-2.0.

A guide to bypassing a web application firewall (WAF), a filter placed in front of a website to detect suspicious requests.

In plain words
What is it for?
It is for identifying WAF products, testing obfuscated requests, discovering origin servers, and evaluating request and anomaly controls.
Why use it?
It helps determine whether a payload is blocked by the WAF, whether the origin can be reached separately, or whether rate limits can be avoided within authorized testing.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Good fit It is for identifying WAF products, testing obfuscated requests, discovering origin servers, and evaluating request and anomaly controls.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/purpleailab/decepticon/waf-bypass
About the project

Decepticon is an autonomous red-team agent that coordinates AI agents, security tools, sandboxes, and supporting services for authorized cybersecurity assessments. Security researchers and red teams can run it through its Docker stack, cloud service, command-line interface, or Python SDK, with the catalogue entries representing its available skills.

PurpleAILAB/Decepticon · 5,497 stars · on GitHub · decepticon.red

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add PurpleAILAB/Decepticon --skill waf-bypass
Clone the repo
git clone --depth 1 https://github.com/PurpleAILAB/Decepticon

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for waf-bypass

README.md
[![agentmods](https://agentmods.dev/badge/skills/purpleailab/decepticon/waf-bypass/github.svg)](https://agentmods.dev/skills/purpleailab/decepticon/waf-bypass)
Your own site
<a href="https://agentmods.dev/skills/purpleailab/decepticon/waf-bypass"><img src="https://agentmods.dev/badge/skills/purpleailab/decepticon/waf-bypass/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for waf-bypass

Your own site · 80×15
<a href="https://agentmods.dev/skills/purpleailab/decepticon/waf-bypass"><img src="https://agentmods.dev/badge/skills/purpleailab/decepticon/waf-bypass.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,846 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 3 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Privilege Escalation · line 54
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • medium Data Exfiltration · line 48
    Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.
    Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
  • medium Data Exfiltration · line 178
    Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.
    Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00048 $0.03846
Opus 5 $0.00024 $0.01923
Sonnet 5 $0.00010 $0.00769
Haiku 4.5 $0.00005 $0.00385

Measured 9d ago against content hash f0ddd4728fa7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

waf-bypass scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -sI "https://<TARGET>/?id=1' OR '1'='1" | grep -iE 'server|cf-ray|x-amzn|akamai|x-sucuri|x-cdn|set-cookie'
packages/decepticon/decepticon/skills/standard/exploit/web/waf-bypass/SKILL.md · 240 lines

How it starts

The opening of the file, as written. The whole thing — 240 lines — stays where its author put it; the contents beside it link to each section on GitHub.

WAF Bypass / Evasion

A WAF is a signature + score engine in front of the origin. Bypass goals: (a) deliver a payload the rule set does not match, (b) reach the origin directly so the WAF is out of band, or (c) keep request rate / anomaly score under thresholds while exfiltrating. OPSEC: this skill is for authorized scope. Stay within rate limits the program allows; never test live customer flows; mark traffic with a researcher header where the program asks for it (X-Bug-Bounty: <HANDLE>).

1. Recon first — fingerprint the WAF

See skills/standard/recon/web-recon/waf-detection/SKILL.md. Without a fingerprint you are guessing. Quick:

wafw00f -a "https://<TARGET>"
curl -sI "https://<TARGET>/?id=1' OR '1'='1" | grep -iE 'server|cf-ray|x-amzn|akamai|x-sucuri|x-cdn|set-cookie'
nuclei -u "https://<TARGET>" -t http/technologies/waf-detect.yaml

Note the stack: WAF vendor, CDN, origin web server, application framework. Each layer has its own parser — bypasses live in the gaps.

2. Payload obfuscation

Layer Technique Example
Case Mixed case on keywords (most modern WAFs are case-insensitive — try anyway) SeLeCt, uNiOn
Whitespace Tab, FF, CR, LF, /**/, +, %a0, %0b, %0c between tokens UNION/**/SELECT, UNION%a0SELECT
Comments Inline SQL comments split keywords UN/**/ION, SEL/*!50000*/ECT (MySQL versioned)
Encoding URL-encode, double-URL-encode, unicode, HTML entity, base64 %2527, %u0027, &#39;, \x27, \u0027
Mixed encoding Encode only the bytes the rule looks for '%20OR%201=1--%27 OR 1%3D1--
Alternate syntax (SQL) UNION-less extraction via boolean/blind, `
Alternate syntax (XSS) Tagless / event-less / template / SVG / MathML <svg/onload=alert(1)>, <details/open/ontoggle=alert(1)>, <style>@import"//x"</style>
String concat Break signatures into pieces '+'al'+'ert'+'(1)+', concat(0x61,0x64,0x6d,0x69,0x6e)
Backtick / quote variants `select`, "select", [select] (MSSQL), N'admin'
Null bytes %00 early-terminates many string ops in C-backed parsers admin%00.png
Charset Submit body in unusual charset; WAF inspects as UTF-8 but app decodes UTF-16 Content-Type: ...; charset=utf-16le
Path normalization ..;/, ..%2f, ..%252f, ;/, // between segments /admin..;/users

Read the full file on GitHub · 240 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 240 lines · 48 tokens per session scan A f0ddd4728fa7

Subscribe to this mod's changes

waf-bypass is a skill published in the GitHub repository PurpleAILAB/Decepticon (5,497 stars, last pushed 13d ago), licensed Apache-2.0. It adds 48 tokens to every session and 3,846 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.