Recon Skills is a pack of security-testing skills covering reconnaissance, web applications, APIs, authentication, vulnerability validation, cloud infrastructure, and reporting. Security professionals use it for authorized assessments of systems they own or have written permission to test. The catalogue entries are individual skills from the pack.
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.
npx skills add uphiago/recon-skills --skill cors-chain-automationgit clone --depth 1 https://github.com/uphiago/recon-skillsWrote 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.
[](https://agentmods.dev/skills/uphiago/recon-skills/cors-chain-automation)<a href="https://agentmods.dev/skills/uphiago/recon-skills/cors-chain-automation"><img src="https://agentmods.dev/badge/skills/uphiago/recon-skills/cors-chain-automation/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.
<a href="https://agentmods.dev/skills/uphiago/recon-skills/cors-chain-automation"><img src="https://agentmods.dev/badge/skills/uphiago/recon-skills/cors-chain-automation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 9 findings, up to medium
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 →
- medium Data Exfiltration · line 72 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 76 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 83 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 104 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 132 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 166 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 316 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 326 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 321 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.
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 5.1 | $0.00024 | $0.03989 |
| Opus 5 | $0.00012 | $0.01995 |
| Sonnet 5 | $0.00005 | $0.00798 |
| Haiku 4.5 | $0.00002 | $0.00399 |
Grade A, and why
cors-chain-automation scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl --max-time 30 --connect-timeout 10 -sk -I "https://$TARGET/wp-json/wp/v2/users" -H "Origin: https://evil.com" | grep -i "access-control" How it starts
The opening of the file, as written. The whole thing — 348 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Multi-Endpoint CORS Triage
When to Use
Use when you have a list of API endpoints or target domains and need to systematically find credential-exploitable CORS misconfigurations at scale. Distinguishes the 3 exploitable patterns (reflect-any-origin + credentials, null-origin trust, subdomain-regex bypass) from false positives (ACAO: * alone, ACAC without reflected origin, same-origin-only). Generates ready-to-use browser PoC HTML files for confirmed findings.
CORS Variations
| # | Variation | Initial signal | Required follow-up |
|---|---|---|---|
| V1 | Origin reflection with credentials | Reflected origin and ACAC: true |
Credentialed browser reads protected data |
| V2 | Null-origin trust | ACAO: null and ACAC: true |
Sandboxed browser proof |
| V3 | Wildcard without credentials | ACAO: * |
Determine whether the data is already public |
| V4 | Credentialed preflight | OPTIONS accepts origin and method | Actual browser request succeeds |
| V5 | Protected-route CORS | CORS appears on a 401 or 403 | Approved session returns protected data |
| V6 | Broad origin reflection | Several unrelated origins are reflected | Controlled-origin browser proof |
| V7 | Namespace-specific CORS | Only one API or plugin namespace reflects | Validate that namespace's data or action |
| V8 | Environment-specific CORS | Policies differ across environments | Demonstrate impact within scope |
Critical Implementation Lesson — Test ALL Endpoints, Not Just /users
Do not infer policy for an entire application from one route. Test the bounded set of endpoints supported by the application map:
# WRONG — tests only /users:
curl --max-time 30 --connect-timeout 10 -sk -I "https://$TARGET/wp-json/wp/v2/users" -H "Origin: https://evil.com" | grep -i "access-control"
# CORRECT — test ALL endpoints:
for ep in /wp-json/wp/v2/users /wp-json/wp/v2/posts /wp-json/wp/v2/pages \
/wp-json/wp/v2/media /wp-json/wp/v2/comments /wp-json/wp/v2/statuses \
/wp-json/wp/v2/tags /wp-json/wp/v2/categories /wp-json/wp/v2/settings \
/wp-json/wc/v3/products /wp-json/gf/v2/forms /wp-json/wp-site-health/v1; do
cors=$(curl --max-time 30 --connect-timeout 10 -sk -I "https://$TARGET${ep}" -H "Origin: https://evil.com" 2>/dev/null | grep -iE "access-control-allow-origin|access-control-allow-credentials")
code=$(curl --max-time 30 --connect-timeout 10 -sk -o /dev/null -w "%{http_code}" "https://$TARGET${ep}" -H "Origin: https://evil.com" 2>/dev/null)
echo "${ep} — HTTP ${code} | ${cors:-NO CORS}"
done
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.
- 12d ago First seen · 348 lines · 24 tokens per session scan A 788e8eb211c1
cors-chain-automation is a skill published in the GitHub repository uphiago/recon-skills (1,254 stars, last pushed 10d ago), licensed MIT. It adds 24 tokens to every session and 3,989 once invoked, about $0.0001 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 2026-08-30.
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