Back to skill

Security audit

Bird

Security checks for vulnerabilities and agentic risk

Overview

Bird actions require appropriate approvals, but automatic CLI setup executes unverified remote code without explaining or separately approving broader local changes.

Review and install the CLI separately before use, and examine its automatic skill synchronization settings. Bird contact data and message payloads pass through OOMOL; grant only needed account permissions and retain the skill's write and deletion confirmations. The remote installer payload was unavailable for inspection. No malicious behavior was established.

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 performs remote installer execution rather than any identifiable Bird operation. Nothing in the supplied material establishes this installer as a supporting dependency for Bird access. The downloaded script's contents are not provided, so its additional effects cannot be determined.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
97% confidence
Finding

The command immediately executes whatever script the remote endpoint returns, without version pinning or independent integrity verification; the PowerShell alternative has the same weakness. HTTPS and the provider-related domain reduce some risks but do not protect against a compromised distribution endpoint or malicious installer update, which could execute code with the agent's local privileges.

Content

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

Fallback setup executes downloaded installer scripts without warning about local system changes.

Medium
Category
Output Handling
Confidence
90% confidence
Finding

The missing-CLI fallback directs the agent to execute a remote installer without explicitly obtaining approval for local software installation or explaining its system changes. Although installation is a legitimate prerequisite and only occurs after a specific failure, it expands a Bird data request into local code execution with the agent's privileges.

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