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Security audit

Hashmob Skill

Security checks for vulnerabilities and agentic risk

Overview

The skill is a HashMob API reference, but it under-warns about account-changing and destructive actions that could affect user data or account value.

Review this skill before installing if you intend to provide a HashMob API key or let an agent run curl commands. Use it only with explicit approval for paid, destructive, withdrawal, purchase, submission, preference, notification, or hashlist-management actions, and verify HashMob's real authorization requirements independently before relying on endpoints marked no API key.

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
Vulnerability Patterns
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
Findings (5)

Intent-Code Divergence

High
Category
Not specified by scanner
Confidence
98% confidence
Finding

The documentation presents destructive DELETE endpoints for hashlists, including a hard-delete variant, as requiring no API key. If an agent trusts this documentation, it may invoke deletion operations without treating them as highly sensitive or requiring user approval, and if the backend actually permits such calls, this would enable unauthorized destruction of data.

Content

No source excerpt is available for this finding.

Description-Behavior Mismatch

Medium
Category
Not specified by scanner
Confidence
95% confidence
Finding

The manifest description says the skill merely lets an agent 'interact with Hashmob.net', but the body documents authenticated endpoints that can spend balance, purchase items, withdraw Gold, submit data, and modify account state. This understatement can mislead users or orchestration systems into granting the skill broader trust than warranted, increasing the chance of unsafe autonomous use.

Content

No source excerpt is available for this finding.

Missing User Warnings

Medium
Category
Not specified by scanner
Confidence
96% confidence
Finding

The skill includes destructive delete and hard-delete examples without adjacent warnings, approval requirements, or explicit guidance that these operations are dangerous. In an agent context, omission of such guardrails materially increases the risk of autonomous or accidental data deletion, especially because the same section also claims no API key is needed.

Content

No source excerpt is available for this finding.

Intent-Code Divergence

Medium
Category
Not specified by scanner
Confidence
86% confidence
Finding

The 'Get user submissions' endpoint is described as requiring no API key even though it appears to expose user-associated submission data. This inconsistency can mislead agents about the sensitivity of the endpoint and, if the backend is similarly exposed, may allow unauthorized access to account-related information.

Content

No source excerpt is available for this finding.

Intent-Code Divergence

Medium
Category
Not specified by scanner
Confidence
90% confidence
Finding

The notifications section labels all endpoints as unauthenticated, including an endpoint that marks unread notifications as read, which is an account-state-changing action. This contradicts the earlier security model and may cause agents to under-classify a state-changing request, leading to unintended modification of user account data or unsafe assumptions about endpoint access control.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.