@extenshi/mcp@0.18.1
Extenshi MCP server — bring the extension catalog (search, security, market research) and pre-publish scanning into your AI tools
AI Security Review
scanned 1d ago · by lpm-firewall-aiThe source shows default-on runtime analytics, while the package README does not disclose telemetry or its opt-out. The collected data appears limited and tool content is filtered, so this is suspicious undisclosed telemetry rather than malicious exfiltration.
Static reason
One or more suspicious static signals were detected.
Trigger
Importing or starting the MCP server; telemetry events are emitted during server startup and tool use unless the user opts out.
Impact
Usage and coarse runtime information is sent to PostHog without disclosure in the package README; users must discover and set an opt-out to disable it.
Mechanism
The package initializes a PostHog client with an embedded project key and sends usage events associated with an anonymous install ID. MCP analytics instrumentation is configured to discard tool arguments, results, and error messages.
AI rationale
The source shows default-on runtime analytics, while the package README does not disclose telemetry or its opt-out. The collected data appears limited and tool content is filtered, so this is suspicious undisclosed telemetry rather than malicious exfiltration.
Evidence
dist/index.jsdist/telemetry.jsdist/mcp-analytics.js~/.extenshi/config.json
Network endpoints1
eu.i.posthog.com
Decision evidence
public snapshotAI called this Suspicious at 91.0% confidence as Dangerous Capability with medium false-positive risk.
Evidence for warning
- The MCP entry point initializes telemetry at startup, and the telemetry module says it is active by default unless opted out.
- Telemetry sends package and runtime details with an anonymous per-install ID; MCP analytics drops tool arguments, results, and error messages.
- The postinstall telemetry ping requires telemetry:true in the existing config, so it does not run without prior recorded consent.
Evidence against
- The runtime telemetry payload is limited to usage, error classification, duration, and coarse runtime details; the MCP analytics instrumentation excludes tool content.
- The publish-access request sends the Extenshi API key to the configured Extenshi BFF as part of the publishing tool’s explicit operation.
Behavioral surface
CryptoDynamicRequireEnvironmentVarsFilesystemNetwork
HighEntropyStringsTelemetryUrlStrings
Source & flagged code
4 flaggedpackage.jsonView file
•scripts.postinstall = node scripts/postinstall.cjs
High
Install Time Lifecycle Scripts
Package defines install-time lifecycle scripts.
package.jsonView on unpkg•scripts.postinstall = node scripts/postinstall.cjs
Medium
Ambiguous Install Lifecycle Script
Install-time lifecycle script is not statically allowlisted and needs review.
package.jsonView on unpkgdist/index.jsView file
30import { checkForUpdate } from './update-check.js';
L31: const require = createRequire(import.meta.url);
L32: const pkg = require('../package.json');
Medium
Dynamic Require
Package source references dynamic require/import behavior.
dist/index.jsView on unpkg · L30Findings
2 High5 Medium6 Low
HighInstall Time Lifecycle Scriptspackage.json
HighSemantic Analysis Limiteddist/development-guide.js#virtual:normalized:round1
MediumAmbiguous Install Lifecycle Scriptpackage.json
MediumDynamic Requiredist/index.js
MediumNetwork
MediumEnvironment Vars
MediumStructural Risk Force Deep Review
LowNon Install Lifecycle Scripts
LowScripts Present
LowFilesystem
LowHigh Entropy Strings
LowTelemetry
LowUrl Strings
Affected versions and remediation
This report applies to @extenshi/mcp@0.18.1.
See all versions of @extenshi/mcp for other recorded verdicts.
- Review the evidence and your use of @extenshi/mcp@0.18.1 before allowing it. Restrict the permissions described in this report.
- Choose an independently verified alternative or release. This report does not establish that other versions are safe.
Evidence last updated: .
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