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Security audit

URL Preview

Security checks for vulnerabilities and agentic risk

Overview

This skill does what it says: it fetches public web links to show a small preview, with no bundled code, persistence, or hidden install behavior.

Install this only if you are comfortable with shared public links being fetched to generate previews. Avoid using it for private, internal, token-bearing, or sensitive URLs unless the host environment prevents those requests.

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
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
Findings (4)

Vague Triggers

Medium
Category
Not specified by scanner
Confidence
94% confidence
Finding

The trigger definition is overly broad because it activates on any shared HTTP/HTTPS link, which can cause the skill to run without clear user intent. That creates privacy and surprise-network-access risks, since merely pasting a URL may cause automatic fetching of third-party content.

Content

No source excerpt is available for this finding.

Vague Triggers

Medium
Category
Not specified by scanner
Confidence
93% confidence
Finding

The instruction to automatically extract content whenever a user shares a URL is ambiguous and unsafe because it removes an explicit confirmation step. In practice, this can lead to unintended requests to attacker-controlled or sensitive URLs, increasing privacy and trust-boundary concerns.

Content

No source excerpt is available for this finding.

Missing User Warnings

Medium
Category
Not specified by scanner
Confidence
91% confidence
Finding

The skill describes fetching and summarizing shared URLs but does not clearly warn the user that it will access the link over the network. This is dangerous because users may not expect external requests to occur, which can leak metadata or trigger requests to tracking or attacker-controlled infrastructure.

Content

No source excerpt is available for this finding.

Natural-Language Policy Violations

Low
Category
Not specified by scanner
Confidence
79% confidence
Finding

The trigger list hard-codes Chinese and English phrases as activation examples, but does not explain language selection or whether other languages are supported. This can create an implicit language policy without user opt-in or documented locale constraints.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.