Back to skill

Security audit

Rentman

Security checks for vulnerabilities and agentic risk

Overview

Rentman access matches the stated purpose, but setup runs downloaded installation code without a clear approval step or limits on broader agent changes.

Review and approve CLI installation separately before allowing setup to proceed. Understand that OOMOL mediates access to your Rentman account. Review the CLI's automatic skill synchronization and its documented controls before use. The remote installers could not be inspected, so their exact changes remain uncertain; the supplied artifacts do not establish malicious intent.

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
  • 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
Findings (5)

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
97% confidence
Finding

The supplied code performs remote software installation rather than Rentman data access. Although installation can be a supporting implementation detail, the chunk establishes no relationship between the Oomol installer and Rentman functionality. The downloaded script's further behavior cannot be determined from the supplied code.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
99% confidence
Finding

The command executes a mutable remote script with the local user's privileges without checking a pinned version, signature, or trusted digest. If the distribution endpoint or release pipeline is compromised, the script could access local credentials, modify files, or establish persistence; the PowerShell alternative has the same issue. HTTPS and conditional installation reduce some exposure but do not verify the script's integrity.

Content

Scanner excerpt · SKILL.md (reported line 62)May include surrounding context.

The setup workflow instructs the agent to execute downloaded installation scripts without warning the user about running remote code or modifying their system.

Medium
Category
Output Handling
Confidence
96% confidence
Finding

The fallback directs the agent to install software by immediately executing downloaded code, without requiring approval for that system-changing operation. A Rentman read request does not itself authorize arbitrary local software installation; although the missing-CLI condition limits exposure, it does not establish user consent.

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 83)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

External Transmission

Medium
Category
Data Exfiltration
Confidence
50% 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 88)May include surrounding context.

md
## Resources

- Rentman homepage: https://rentman.io
- API documentation: https://api.rentman.net/