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Security audit

NetEase Mail

Security checks for vulnerabilities and agentic risk

Overview

The mail controls are sensible, but setup directs the agent to execute an unverified online installer without separate user approval.

Review and install the CLI separately before allowing mail tasks to trigger setup. Understand that OOMOL handles the connected account, and retain confirmation for sending, changing, moving, or deleting mail. The remote installer and hosted connector were not bundled for inspection; the Review verdict concerns setup control, not demonstrated malicious behavior.

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
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • Output HandlingUnvalidated Output Injection, Cross-Context Output, Unbounded Output
  • MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
Findings (4)

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
96% confidence
Finding

The supplied chunk performs remote script execution rather than any demonstrated NetEase Mail operation. Although installing a dependency could be a supporting implementation detail, nothing supplied establishes this installer as a dependency for the declared mail functionality. The downloaded script's contents are unavailable, so its further behavior cannot be determined.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
98% confidence
Finding

Piping a mutable HTTPS installer directly into bash executes remote code without version pinning or independent integrity verification; the PowerShell example has the same weakness. Compromise of the distribution endpoint could yield arbitrary execution with the invoking user's privileges, potentially exposing local files and credentials, although the conditional setup path and declared oo-only tool restriction limit immediate reachability.

Content

Scanner excerpt · SKILL.md (reported line 66)May include surrounding context.

The setup workflow executes downloaded installation scripts without warning about local system changes or remote code execution.

Medium
Category
Output Handling
Confidence
93% confidence
Finding

The missing-CLI fallback directs installation through remotely downloaded shell or PowerShell code without explaining local changes or requiring explicit installation approval. Although this runs only after a missing-command error, a mail-management request should not implicitly authorize executing installation code on the user's machine.

Content

No source excerpt is available for this finding.

Autonomous Decision Making

Medium
Category
Excessive Agency
Confidence
80% confidence
Finding

Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.

Content

Scanner excerpt · SKILL.md (reported line 87)May include surrounding context.

md
- **`OOMOL_INSUFFICIENT_CREDIT`** — OOMOL billing stop. Recharge at `https://console.oomol.com/billing/token-recharge` before retrying.

- **HTTP 402 without `OOMOL_INSUFFICIENT_CREDIT`** — the third-party account itself has no active plan or credit. Report the provider error message as is; do not ask the user to recharge OOMOL.

## Resources