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Security audit

China Mirror

Security checks for vulnerabilities and agentic risk

Overview

This skill openly changes generated install and download commands to use China-based mirrors, so it should only be enabled by users who want that routing.

Install this only if you intentionally want your agent to prefer the listed China-based mirrors for package downloads. Review generated install commands before running them when dependency provenance matters, and explicitly specify an upstream source when you do not want mirror substitution.

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
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
  • Rogue AgentSelf-Modification, Session Persistence
  • Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
Findings (10)

Natural-Language Policy Violations

Medium
Category
Not specified by scanner
Confidence
91% confidence
Finding

The skill is presented as a China-specific solution and states that AI-generated commands should automatically add domestic mirror source parameters. This imposes a locale-specific behavior by default, but the README does not indicate user opt-in, language/region selection, or a clearly scoped regional-compliance justification.

Content

No source excerpt is available for this finding.

Rp1

Medium
Category
MCP Rug Pull
Confidence
75% confidence
Finding

Docker image references without a specific tag (:latest is implicit) or digest (@sha256:...) can be silently replaced by a malicious image.

Content

No source excerpt is available for this finding.

Session Persistence

Medium
Category
Rogue Agent
Confidence
86% confidence
Finding

These commands establish lasting integration with both ~/.agents/skills and optionally ~/.claude/skills, which extends the skill's influence beyond a one-time run. While likely intended for convenience, persistent registration is security-relevant because any future changes to the linked repository are automatically trusted by the agent runtime.

Content

Scanner excerpt · README.md (reported line 31)May include surrounding context.

md
git clone https://github.com/xiaomiba0904/china-mirror-skill.git

# 安装到 Claude Code skills 目录
mkdir -p ~/.agents/skills
ln -s $(pwd)/china-mirror-skill ~/.agents/skills/china-mirror

# 可选:创建符号链接到 .claude/skills

Session Persistence

Medium
Category
Rogue Agent
Confidence
86% confidence
Finding

These commands establish lasting integration with both ~/.agents/skills and optionally ~/.claude/skills, which extends the skill's influence beyond a one-time run. While likely intended for convenience, persistent registration is security-relevant because any future changes to the linked repository are automatically trusted by the agent runtime.

Content

Scanner excerpt · README.md (reported line 31)May include surrounding context.

md
git clone https://github.com/xiaomiba0904/china-mirror-skill.git

# 安装到 Claude Code skills 目录
mkdir -p ~/.agents/skills
ln -s $(pwd)/china-mirror-skill ~/.agents/skills/china-mirror

# 可选:创建符号链接到 .claude/skills

Skill Enumeration

Medium
Category
Agent Snooping
Confidence
85% confidence
Finding

Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.

Content

Scanner excerpt · README.md (reported line 34)May include surrounding context.

mkdir -p ~/.agents/skills ln -s $(pwd)/china-mirror-skill ~/.agents/skills/china-mirror

可选:创建符号链接到 .claude/skills

mkdir -p ~/.claude/skills ln -s ~/.agents/skills/china-mirror ~/.claude/skills/china-mirror

text

Rp1

Medium
Category
MCP Rug Pull
Confidence
75% confidence
Finding

Docker image references without a specific tag (:latest is implicit) or digest (@sha256:...) can be silently replaced by a malicious image.

Content

No source excerpt is available for this finding.

Natural-Language Policy Violations

Medium
Category
Not specified by scanner
Confidence
94% confidence
Finding

The skill hard-codes a China-specific mirror policy in its metadata/description without any user opt-in, locale check, or disclosure that generated install commands will be rewritten to use alternate registries. This can silently redirect package downloads away from official upstream sources, affecting supply-chain trust, reproducibility, compliance, and reliability for users outside the intended region.

Content

No source excerpt is available for this finding.

Natural-Language Policy Violations

Medium
Category
Not specified by scanner
Confidence
97% confidence
Finding

The rule requiring automatic use of domestic mirrors for any command that may trigger a download creates an undisclosed regional default that overrides normal package source expectations. Because the skill applies this broadly, including indirect download scenarios, it increases the chance of silently changing dependency provenance and causing users to execute commands against unintended registries or mirrors.

Content

No source excerpt is available for this finding.

Vague Triggers

Medium
Category
Not specified by scanner
Confidence
95% confidence
Finding

The description says the skill will automatically add mirror parameters whenever the AI generates package download commands, which is an overly broad activation condition. Automatically rewriting install commands can silently redirect users to alternate infrastructure, reducing user awareness and weakening trust boundaries even if the mirrors are described as reputable.

Content

No source excerpt is available for this finding.

Natural-Language Policy Violations

Medium
Category
Not specified by scanner
Confidence
88% confidence
Finding

The description presents China-specific mirror use as default behavior without mentioning user choice, consent, or fallback to upstream sources. In a skill that influences software installation commands, forcing region-specific mirrors can cause users to fetch packages from unintended sources, with supply-chain and integrity risks if the substitution is not explicitly requested and reviewable.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.