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Security audit

Brevo

Security checks for vulnerabilities and agentic risk

Overview

The Brevo operations have clear approval safeguards, but setup can execute unverified remote code and introduce broader changes to your agent environment.

Review and approve CLI installation separately, using an inspected, verified release. Consider whether OOMOL should handle your Brevo connection and contact data. Upstream documents OO_SKILLS_SYNC_DISABLED as a control against automatic skill synchronization. The downloaded installer and hosted connector implementation remain unverified. [CLI controls](https://github.com/oomol-lab/oo-cli/blob/main/docs/commands.md)

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
98% confidence
Finding

The supplied code's sole visible action is remote installer execution, which is materially different from the declared Brevo functionality. Nothing in the chunk establishes this installer as a supporting dependency for Brevo operations. The downloaded script's contents and further effects cannot be determined from the supplied code.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
98% confidence
Finding

Piping a live remote script directly into Bash executes whatever the installation endpoint supplies with the invoking user's permissions, without a pinned version or independent integrity verification. Compromise of the vendor endpoint or distribution pipeline could therefore compromise the local host; HTTPS protects transport but does not establish script trustworthiness. The PowerShell installation alternative has the same underlying issue.

Content

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

First-time setup executes downloaded installation scripts without warning about remote code execution or local system changes.

Medium
Category
Output Handling
Confidence
94% confidence
Finding

The missing-command fallback directs installation without requiring user approval or explaining that downloaded code will execute locally and may modify the system. Restricting installation to first-time setup reduces exposure, but authorization to operate Brevo does not necessarily authorize installing software on the host.

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