A command-line scanner for checking whether a web API's cross-origin sharing rules let an untrusted website read its responses. CORS is the browser rule that controls which other websites may access an API.

Use it to scan one API endpoint or a list of endpoints, optionally with a session cookie, and inspect the server's CORS responses.

It helps find unsafe origin checks, credential exposure, and scheme or subdomain bypasses that could expose data from logged-in users.

cors — Command by Awarexone

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.

agentmods

npx agentmods add commands/awarexone/agentic-bug-hunter/cors

Clone the repo

git clone --depth 1 https://github.com/Awarexone/Agentic-Bug-Hunter

Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 527 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 1 finding. Scan, not verified.

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.

Model	Per session	Once invoked
Fable 5	$0.00000	$0.00527
Opus 5	$0.00000	$0.00264
Sonnet 5	$0.00000	$0.00105
Haiku 4.5	$0.00000	$0.00053

Measured 3d ago against content hash ea693fb0c65c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cors 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 3d 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.

`ACAO: <attacker>` + `ACAC: true` means `fetch(url, {credentials:'include'})`

commands/cors.md · 54 lines

What it actually says

/cors

Find CORS misconfigurations that let an attacker page read authenticated responses cross-origin. Sends a battery of crafted Origin headers and inspects the Access-Control-Allow-Origin / Access-Control-Allow-Credentials reply.

Usage

/cors https://api.target.com/me
/cors https://api.target.com/me --cookie "session=abcd1234"
/cors -l recon/target.com/urls/api-endpoints.txt --json

Run directly:

tools/cors_scanner.py https://api.target.com/me --cookie "session=..."

What it tests

Origin sent	Detects
`https://evil.example`	arbitrary-origin reflection
`null`	sandboxed-iframe / data: URI trust
`https://api.target.com.evil.example`	weak `endsWith` (suffix) regex
`https://notapi.target.com`	weak `startsWith` (prefix) regex
`https://attacker.api.target.com`	blanket subdomain trust (chains w/ takeover)
`http://api.target.com`	https→http scheme downgrade

Severity

CRITICAL — reflects attacker origin with ACAC: true (cookie-auth cross-origin read).
HIGH — null origin trusted with credentials.
MEDIUM — reflects attacker origin without credentials (exploitable when auth is a non-cookie token), or trusts http downgrade.
INFO — ACAO: * with no credentials (usually intended public CORS).

Why a credentialed reflection is the win

ACAO: <attacker> + ACAC: true means fetch(url, {credentials:'include'}) from an attacker page returns the victim's authenticated response body — full account-data exfil. Pass --cookie with a live session to confirm the credentialed path.

Chain

CORS data-read → harvest CSRF token / PII / API keys from the response → escalate to ATO. A subdomain-trust CORS bug + a subdomain takeover on that subdomain = a clean credentialed-read exploit.

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.

3d ago First seen · 54 lines · 0 tokens per session scan A ea693fb0c65c

Subscribe to this mod's changes

cors is a command published in the GitHub repository Awarexone/Agentic-Bug-Hunter (4,651 stars, last pushed yesterday), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 527 tokens. 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 2026-08-30.

Security ai-security bug-bounty bugcrowd claude-ai claude-code cti

recon

Run full recon pipeline on a target — subdomain enum (Chaos API + subfinder), live host discovery (dnsx + httpx), URL crawl (katana + waybackurls + gau), gf pattern classification, nuclei scan. Outputs to recon/ / directory. Usage: /recon target.com.

elementalsouls/Claude-BugHunter · 65 tokens

hunt

Active vulnerability hunting. Two-track dispatcher — asks Red Team vs WAPT, hands off to hunt-dispatch skill and sibling commands. Usage: /hunt target.com | /hunt .target.com | /hunt targets.txt [--vuln-class X] [--source-code P] [--chrome].

elementalsouls/Claude-BugHunter · 63 tokens

token-scan

Meme coin and token security scan — checks for rug pull vectors (hidden mint, honeypot, fee manipulation, LP lock bypass, authority retention, bonding curve exploits, fake renounce, sandwich amplification). Manual 8-class grep audit (with an optional automated scanner if present). Usage: /token-scan [--chain solana].

elementalsouls/Claude-BugHunter · 79 tokens

cors