Security audit

hookpipe

Security checks for vulnerabilities and agentic risk

Overview

The skill is purpose-aligned webhook tooling, but it deserves review because it installs an unpinned external CLI and repeatedly shows secrets and tokens being entered directly in shell commands.

Review the hookpipe package provenance before installing, prefer a pinned and verified release if available, and avoid putting real webhook secrets or API tokens directly in shell commands. Use a secret manager, protected file, or interactive prompt if the CLI supports it, and keep provider/event filters narrow so only intended webhook events reach the agent.

A.I.G

Vulnerability Patterns

Insecure DependenciesIntroduces malicious components through unsafe dependency sources
Insecure Skill Coding PracticesFinds exploitable flaws such as hardcoded secrets or command injection
Skill Instruction HijackingAlters the agent's session goals or safety constraints when the skill loads
Agent Memory PoisoningWrites attacker-controlled rules into memory that affect later sessions
Remote Payload Retrieval and ExecutionFetches external code whose behavior can change after review

Findings (2)

T08 · Insecure Dependencies

Warning

Location: SKILL.md:9
Finding: Unpinned External CLI Installation Creates a Mutable Supply-Chain Risk
Content: View full analysis
Remediation: View remediation

T09 · Insecure Skill Coding Practices

Warning

Location: SKILL.md:35
Finding: Sensitive Credentials Are Passed Through Command-Line Arguments
Content: View full analysis
Remediation: View remediation
` with safer workflows, such as: ```bash hookpipe connect stripe --secret-file ~/.config/hookpipe/stripe-secret ``` or an interactive prompt: ```bash hookpipe connect stripe --prompt-secret ``` 6. Ensure the CLI redacts credentials from output, errors, telemetry, debug logs, and generated configuration displays. 7. Store persistent tokens in a credential store or a file with restrictive permissions rather than plaintext configuration. 8. Add explicit warnings against entering secrets in shared terminals, recorded sessions, shell tracing contexts, or CI command lines. 9. Rotate any credential that may already have been exposed through shell history or logs, and securely remove retained copies where feasible. ]]>

SkillSpector

Vulnerability Patterns

Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code

Findings (1)

Scope Creep

Low

Category: Excessive Agency
Confidence: 70% confidence
Finding: Skill's behavior or capabilities extend beyond its stated purpose. Scope creep allows an agent to perform actions unrelated to its documented functionality, increasing the attack surface.
Content: Scanner excerpt · SKILL.md (reported line 79)May include surrounding context.
Any other webhook service

Not limited to the 5 built-in providers. For any service already sending webhooks to your agent, use generic HMAC verification:

bash
hookpipe connect my-service --secret my_signing_secret --to http://localhost:18789/webhook

Static analysis

No suspicious patterns detected.