hunt-ssti
Hunt server-side template injection (SSTI) across Jinja2 (Flask/Django), Twig (Symfony), Freemarker (Java), ERB (Rails), Spring, Velocity, Mako, Thymeleaf, Smarty. Detection probes use double-curly and dollar-curly math expressions evaluated server-side. Once an engine is fingerprinted, escalate to RCE via the engine-specific class-walker, callback-registrar, or Execute-utility patterns documented in disclosed reports. Detection patterns: error messages reveal engine, blank or numeric eval reveals expression mode. Targets: email templates, PDF/report generators, CMS preview features, error pages with user input. Use when hunting RCE via template rendering, when content shows engine fingerprints, when finding endpoints that compose strings with user input before render.
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E004: Prompt injection detected in skill instructions.
What this means
Detected a prompt injection in the skill instructions. The skill contains hidden or deceptive instructions that fall outside its stated purpose and attempt to override the agent’s safety guidelines or intended behavior.
Why it was flagged
This skill contains explicit, actionable exploitation instructions and payloads to escalate server-side template injections to remote code execution and data exfiltration.
E006: Malicious code pattern detected in skill scripts.
What this means
Detected high-risk code patterns in the skill content — including its prompts, tool definitions, and resources — such as data exfiltration, backdoors, remote code execution, credential theft, system compromise, supply chain attacks, and obfuscation techniques.
Why it was flagged
The document explicitly instructs attackers to "escalate straight to RCE" and supplies concrete, executable SSTI payloads (e.g., Jinja2 os.popen snippets and Freemarker Execute calls) that, when submitted to a vulnerable server, will run shell commands—showing clear malicious intent and a viable runtime mechanism.
W011: Third-party content exposure detected (indirect prompt injection risk).
What this means
The skill exposes the agent to untrusted, user-generated content from public third-party sources, creating a risk of indirect prompt injection. This includes browsing arbitrary URLs, reading social media posts or forum comments, and analyzing content from unknown websites.
Why it was flagged
The skill “hunt-ssti” describes probing and escalating SSTI by injecting attacker-controlled payloads into application inputs (e.g., email templates and template-preview forms) and then reading the evaluated output, which means outsider-authored free text is ingested at runtime by the target application’s template rendering workflow without any prior selection/allowlisting.
- Repository
- elementalsouls/Claude-BugHunter
- Commit
d4b54e1
- Audited
- Security analysis
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