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Security audit

Shotstack

Security checks for vulnerabilities and agentic risk

Overview

The Shotstack workflow is coherent, but its setup instructions can trigger execution of an unverified remote installer without separate approval.

Review and install the required CLI yourself before use, including its automatic skill-installation behavior. Require explicit approval for any installer execution. OOMOL mediates your Shotstack connection and submitted data; verify its account permissions and review each render payload and expected charges. The concern is insufficient control over setup, with no artifact-backed evidence of 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
  • 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
96% confidence
Finding

The declared purpose concerns Shotstack operations, but the supplied code executes an Oomol-hosted installation script. Nothing in the chunk establishes this as a supporting dependency for Shotstack. The installer’s contents and any subsequent behavior are not provided.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
99% confidence
Finding

The command pipes a remotely fetched, unpinned script directly into Bash without inspecting or independently verifying its contents; the PowerShell setup uses the equivalent download-and-execute pattern. A compromised installer endpoint or release pipeline could execute arbitrary code with the invoking user's permissions, including accessing local files and credentials; HTTPS alone does not establish that the script is trustworthy.

Content

Scanner excerpt · SKILL.md (reported line 56)May include surrounding context.

First-time setup executes downloaded installation scripts without warning about system-level effects.

Medium
Category
Output Handling
Confidence
94% confidence
Finding

On a missing-CLI error, the skill directs installation without requiring explicit user approval or explaining that downloaded code will execute locally and may modify the environment. The error-triggered setup condition limits exposure, but confirmation requirements for Shotstack writes do not protect this separate local execution path.

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 77)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