Back to skill

Security audit

SendGrid

Security checks for vulnerabilities and agentic risk

Overview

The SendGrid workflow has appropriate confirmation steps, but its fallback setup tells the agent to run downloaded installation code without asking first.

Review and approve CLI installation separately before using the missing-dependency fallback, including its automatic skill synchronization. Use a verified release and narrowly scoped SendGrid credentials, and retain confirmation before sending email. The Review verdict concerns setup control and unverified downstream installation effects; the supplied 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
99% confidence
Finding

The supplied command installs software from an external CLI provider; it does not show any SendGrid operations or establish that this installation supports them. Executing a remote installer is a materially different capability from the declared purpose. The downloaded script's contents and further effects are not provided 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 a live download directly into Bash executes whatever the installation endpoint returns, without a pinned version, independent integrity check, or review; the PowerShell alternative has the same weakness. If the endpoint or distribution pipeline is compromised, execution could expose local files and credentials or modify the host with the agent's privileges, although this path is conditional and may be blocked by the declared tool allowlist.

Content

Scanner excerpt · SKILL.md (reported line 58)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
91% confidence
Finding

The fallback directs the agent to install software through remotely supplied scripts without requiring approval for local code execution or explaining potential system changes. Although conditional on a missing dependency, it extends a SendGrid task into local software installation; strict enforcement of the declared Bash(oo *) permission would limit execution of the shown installer commands.

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 79)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