Back to skill

Security audit

Documenso

Security checks for vulnerabilities and agentic risk

Overview

If its required CLI is missing, this skill directs your agent to execute a downloaded installer without first asking for approval.

Review and install the CLI yourself before use, and require approval for setup changes. Review its automatic skill synchronization settings. Connecting Documenso also entrusts OOMOL with account credentials and access to requested data. The concerns warrant review, but the artifact does not establish 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
99% confidence
Finding

The supplied command performs remote installer execution, not Documenso data retrieval. No connection between this installation and the declared Documenso functionality is shown, so it cannot be established as a supporting implementation detail. The downloaded script's contents and further effects are not available for assessment.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
98% confidence
Finding

Piping a remotely fetched script directly into Bash executes its contents without a review step, version pinning, or independent integrity verification. If the installer endpoint or publishing pipeline is compromised, the script can execute arbitrary code with the invoking user's permissions; HTTPS does not protect against a compromised publisher. The missing-CLI condition limits exposure but does not remove this supply-chain risk, and the PowerShell alternative has the same issue.

Content

Scanner excerpt · SKILL.md (reported line 58)May include surrounding context.

The setup fallback executes downloaded installation scripts without warning the user about system changes or remote-code execution.

Medium
Category
Output Handling
Confidence
95% confidence
Finding

The fallback directs the agent to install software after a missing-command error without first explaining system changes or obtaining installation approval. Although conditional and relevant to the workflow, installing software exceeds the expected scope of searching and reading Documenso data.

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