Security audit

Neckr0ik Newsletter Manager

Security checks across malware telemetry and agentic risk

Overview

This appears to be legitimate newsletter tooling, but it handles subscriber data and email-service credentials without enough disclosure, safeguards, or user control.

Review carefully before installing. Use test credentials, avoid production subscriber lists until you understand the ~/.newsletter-manager storage, review generated content and links manually, and require an explicit test send before any real broadcast.

SkillSpector

By NVIDIA

Vulnerability Patterns

Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
MCP Least PrivilegeUnderdeclared Capability, Wildcard Permission, Missing Permission Declaration
MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access

Findings (5)

Lp3

Medium

Category: MCP Least Privilege
Confidence: 88% confidence
Finding: The skill documentation advertises file read/write and shell-capable operations but declares no permissions, which undermines least-privilege controls and prevents users or a host platform from accurately assessing what the skill can do. In a skill that handles subscriber data, templates, configs, and sending workflows, undeclared capabilities increase the risk of unauthorized local file access or command execution if the implementation follows the documented behavior.

Tp4

High

Category: MCP Tool Poisoning
Confidence: 81% confidence
Finding: The documented behavior exceeds or differs from the stated purpose by including local subscriber persistence, config management, Mailchimp support, and simulated analytics. This mismatch is security-relevant because users may grant trust based on a narrower description while the skill processes personal data locally and handles credentials in ways not clearly disclosed.

Missing User Warnings

Medium

Confidence: 84% confidence
Finding: The skill describes importing/exporting subscribers and sending to all subscribers without any warning about personal data handling, consent, or the consequences of bulk delivery. In the newsletter context, this makes accidental privacy violations, misdirected sends, and noncompliant email operations more likely because the feature is inherently sensitive and high-impact.

Missing User Warnings

Medium

Confidence: 90% confidence
Finding: The documentation instructs users to set API keys and secrets but gives no warning that these credentials are sensitive or how they are protected. In a multi-platform newsletter tool, exposed provider credentials could allow unauthorized sends, subscriber data access, account takeover actions, or abuse across connected email platforms.

Missing User Warnings

Medium

Confidence: 87% confidence
Finding: The importer writes subscriber email addresses and names to disk as plaintext JSON files without any consent notice, retention controls, or file-permission hardening. In a newsletter-management context this handles real personal data, so silent local persistence increases privacy and compliance risk if the workstation, account, or backup set is exposed.

VirusTotal

65/65 vendors flagged this skill as clean.

View on VirusTotal

Static analysis

No suspicious patterns detected.