ClawHub
Back to skill

Security audit

Machine Payments Protocol Tester

Security checks for vulnerabilities and agentic risk

Overview

The skill is a coherent payment-test helper that discloses its external service use and real-money mainnet cost, with no evidence of hidden persistence, credential theft, or destructive behavior.

Install only if you are comfortable using an external payment-testing service. Prefer devnet for dry runs, confirm before any mainnet wallet payment, avoid putting secrets or private identifiers in the optional label, and treat MPP_BASE_URL as trusted configuration if you override it.

A.I.G

Vulnerability Patterns
  • 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
  • Embedded Malicious CodeShips malicious scripts inside the skill and executes them locally
  • Unauthorized Access and Privilege EscalationObtains permissions beyond the task's legitimate needs

SkillSpector

Vulnerability Patterns
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
  • MCP Least PrivilegeUnderdeclared Capability, Wildcard Permission, Missing Permission Declaration
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
Findings (7)

Ae1

High
Category
analysis-evasion
Confidence
100% confidence
Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 29)May include surrounding context.

md
scripts/run-test.sh mainnet-beta

Ae1

High
Category
analysis-evasion
Confidence
100% confidence
Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 30)May include surrounding context.

md
scripts/run-test.sh mainnet-beta

External Script Fetching

High
Category
Supply Chain
Confidence
90% confidence
Finding

Remote code is downloaded and executed. This bypasses code review and could introduce malicious code.

Content

Scanner excerpt · scripts/run-test.sh (reported line 18)May include surrounding context.

sh
esac

echo "Starting $NETWORK MPP test…"
START=$(curl -s -X POST "$BASE/api/mpp/start" \
  -H 'Content-Type: application/json' \
  -d "{\"network\":\"$NETWORK\",\"label\":\"$LABEL\"}")

External Script Fetching

High
Category
Supply Chain
Confidence
90% confidence
Finding

Remote code is downloaded and executed. This bypasses code review and could introduce malicious code.

Content

Scanner excerpt · scripts/run-test.sh (reported line 36)May include surrounding context.

sh
for i in $(seq 1 120); do
  sleep 5
  RESP=$(curl -s "$BASE/api/mpp/tests/$REF")
  STATUS=$(printf '%s' "$RESP" | python3 -c "import sys,json;print(json.load(sys.stdin).get('status',''))")
  case "$STATUS" in
    confirmed)

Undeclared Tool Scope

Medium
Category
MCP Least Privilege
Confidence
91% confidence
Finding

The skill documents shell-based execution paths, including a helper script and curl commands, but does not declare any tool scope or allowed-tools restrictions. That mismatch can cause an agent platform to permit broader execution than intended, increasing the risk of unintended command execution or network access when the skill is invoked.

Content

No source excerpt is available for this finding.

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% confidence
Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 39)May include surrounding context.

1. Start the test

bash
curl -s -X POST https://mpptester.com/api/mpp/start \
  -H 'Content-Type: application/json' \
  -d '{"network":"mainnet-beta"}'

External Transmission

Medium
Category
Data Exfiltration
Confidence
93% confidence
Finding

The script transmits user-controlled data (LABEL) and operational metadata (NETWORK) to an external service at mpptester.com, and the destination can be overridden via MPP_BASE_URL. While this is core to the skill's purpose, it still creates a real data exfiltration and trust-boundary risk because users may unknowingly send sensitive labels or interact with an attacker-controlled endpoint if the environment variable is modified.

Content

Scanner excerpt · scripts/run-test.sh (reported line 18)May include surrounding context.

sh
esac

echo "Starting $NETWORK MPP test…"
START=$(curl -s -X POST "$BASE/api/mpp/start" \
  -H 'Content-Type: application/json' \
  -d "{\"network\":\"$NETWORK\",\"label\":\"$LABEL\"}")

Static analysis

No suspicious patterns detected.