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Security audit

ntfy

Security checks for vulnerabilities and agentic risk

Overview

The notification features fit the stated purpose, but automatic setup executes unverified downloads and can introduce broader agent changes.

Review the CLI installation before allowing automatic setup, including its changes to other agents' skills. The publisher documents OO_SKILLS_SYNC_DISABLED for disabling startup skill synchronization in its [command reference](https://github.com/oomol-lab/oo-cli/blob/main/docs/commands.md). OOMOL mediates notification requests and connected credentials. Confirm the destination and message before publishing. The downloaded installers and remote service implementation were not inspected; 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
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • 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
Findings (6)

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
99% confidence
Finding

The supplied command executes an installer hosted on cli.oomol.com. Nothing in the chunk performs ntfy operations or establishes that this installation supports them. Its observable purpose and accessed resource therefore differ materially from the declared ntfy functionality. The installer's additional effects cannot be determined from this chunk.

Content

No source excerpt is available for this finding.

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
88% confidence
Finding

The supplied chunk performs only an authentication command, rather than the declared ntfy data operations. Authentication could be a supporting implementation detail, but nothing in this chunk connects the oo login to ntfy or establishes it as a prerequisite.

Content

No source excerpt is available for this finding.

Credential Access

High
Category
Privilege Escalation
Confidence
70% confidence
Finding

Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Content

Scanner excerpt · SKILL.md (reported line 40)May include surrounding context.

md
## Available actions

- `get_account` — Retrieve ntfy account profile, limits, and usage for the access token.
- `publish_message` — Publish a notification message to a ntfy topic. [write]

## Safety

External Script Fetching

High
Category
Supply Chain
Confidence
98% confidence
Finding

Piping a remotely fetched installer directly into bash executes its contents without prior inspection or independent integrity verification. HTTPS protects transport but does not protect against compromise of the distribution service; the conditional setup context reduces exposure frequency but not the potential impact.

Content

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

Fallback setup executes downloaded installation scripts without a system-integrity warning.

Medium
Category
Output Handling
Confidence
94% confidence
Finding

The fallback instructs the agent to execute downloaded shell or PowerShell code without an explicit installation approval step or independent integrity verification. Although this is legitimate dependency setup and only runs when the CLI is missing, a compromised distribution endpoint could execute arbitrary code with the invoking user's privileges; the substantive issue is execution control, not merely the missing warning.

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