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Security audit

Cubox

Security checks for vulnerabilities and agentic risk

Overview

The skill requires approval for Cubox changes, but its setup can execute unpinned remote installers without separate user approval.

Review before installing. Preinstall a trusted, version-pinned CLI through an approved process and require separate approval for software installation or changes to other agent skills. Cubox requests pass through OOMOL, so review the connected account's permissions and approve each write payload. The external installers and hosted backend remain unverified; the artifact does not establish 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
94% confidence
Finding

The supplied chunk performs remote installer execution rather than any visible Cubox operation. Dependency installation could be a supporting implementation detail, but the provided content does not establish that this installer supports Cubox functionality. The remote script's contents and downstream effects are not available and cannot be determined from this chunk.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
98% confidence
Finding

Piping an HTTPS response directly into bash executes mutable remote code with the agent process's local privileges, without a pinned version or independent integrity verification. A compromised distribution endpoint could therefore execute arbitrary commands and access local data; the legitimate CLI dependency and missing-command condition limit exposure but do not eliminate it. The PowerShell installation alternative has the same underlying risk.

Content

Scanner excerpt · SKILL.md (reported line 55)May include surrounding context.

The setup workflow runs downloaded installation scripts without warning about local code execution and system changes.

Medium
Category
Output Handling
Confidence
93% confidence
Finding

The missing-CLI fallback directs the agent to execute a downloaded installer without explaining its local execution privileges or obtaining installation-specific approval. Although dependency installation is relevant to Cubox access, consent to a Cubox operation does not necessarily authorize local software installation and system changes.

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 76)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