ssti-error-based-detection

90 / 100 · Low risk

Fine to try. Some of what it can do is expected: a security skill usually runs scanners and checks websites.

By dreadnode/capabilities (GitHub) · security · 22 stars · scanned at commit 3ceeb34

Error-based blind SSTI detection using polyglot payloads and error message differentials to fingerprint template engines. Use when template injection is suspected but output appears blind, or when you need to identify the template engine before escalation.

Works with any agent that supports SKILL.md skills.

What this skill can do

Sends data to these websites: target.com

The author does not mention this. Expected for a security skill.

Found in 6 places.

capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 19curl -x localhost:8080 -k "https://target.com/endpoint" \
capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 28curl -s "https://target.com/endpoint" -d "input={{7*'7'}}" | rg -i "UndefinedError|jinja2"
capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 31curl -s "https://target.com/endpoint" -d "input={{7*7}}" | rg -i "Twig_Error|twig"

Show 3 more

capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 34curl -s "https://target.com/endpoint" -d 'input=${7*7}' | rg -i "ParseException|freemarker"
capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 37curl -s "https://target.com/endpoint" -d 'input=<%= 7*7 %>' | rg -i "SyntaxError|erb"
capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 40curl -s "https://target.com/endpoint" -d 'input=#set($x=7*7)$x' | rg -i "MethodInvocation|velocity"

Runs commands on your computer

The author does not mention this. Expected for a security skill.

Found in 2 places.

capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 19curl -x localhost:8080 -k "https://target.com/endpoint" \
capabilities/web-security/skills/ssti-error-based-detection/SKILL.md, line 28curl -s "https://target.com/endpoint" -d "input={{7*'7'}}" | rg -i "UndefinedError|jinja2"

Install

Paste this into your terminal. It downloads exactly the version we scanned, not whatever is newest.

if [ -e ~/.agents/skills/'ssti-error-based-detection' ] || [ -L ~/.agents/skills/'ssti-error-based-detection' ]; then echo 'A skill folder named ssti-error-based-detection already exists — not replacing it' >&2; false; else d=$(mktemp -d) && git clone --quiet --filter=blob:none --no-checkout 'https://github.com/dreadnode/capabilities' "$d" && git -C "$d" checkout --quiet '3ceeb34c0c33dc36738cf0d4ec86e38b53d98216' -- 'capabilities/web-security/skills/ssti-error-based-detection' && mkdir -p ~/.agents/skills && cp -R "$d"/'capabilities/web-security/skills/ssti-error-based-detection' ~/.agents/skills/'ssti-error-based-detection' && rm -rf "$d"; fi

Codex reads ~/.agents/skills directly. For Claude Code, Cursor, Copilot, Gemini CLI, Antigravity or OpenCode, also link it. For Claude Code: ln -s ~/.agents/skills/'ssti-error-based-detection' ~/.claude/skills/'ssti-error-based-detection' (other agents: ~/.cursor/skills, ~/.copilot/skills, ~/.gemini/skills, ~/.gemini/config/skills, ~/.config/opencode/skills). Or install through the finder skill, which does both.

Badge for your README

The badge for dreadnode/capabilities shows the score of its lowest-scoring skill.

SkillTrust badge for dreadnode/capabilities

[![SkillTrust](https://zalavijaysinh.github.io/skilltrust/badges/dreadnode/capabilities.svg)](https://zalavijaysinh.github.io/skilltrust/repos/dreadnode/capabilities/)

Score history

Date	Version	Score
2026-11-11	`3ceeb34`	90