Crx MCP Server
crx-mcp
npm
v0.3.1
Published by an unidentified publisher — no publish provenance and no public repository, so the publisher could not be verified and the source cannot be independently located.
The grade answers one question — how safe is this server for you to adopt — so it is computed in two auditable stages. Nothing below is an opinion or an LLM's guess; every line is a real term the deterministic engine applied, and the same input always yields the same number.
1. Threat score — 100 − 0 = 100. What the published surface and source actually contain:
The deterministic scan raised no scored threat in the surface it inspected — the threat score stayed at 100. Capability observations and advisory notes are recorded but never lower it.
2. Client adoption risk — 100 − 8 = 92. Three small, subtract-only factors that reflect your risk in adopting it — a clean scan proves less on a powerful, unverified or barely-inspectable package, so the grade says so plainly:
| Points | Adoption-risk factor |
|---|---|
| −6 | capability blast radius (high) — client exposure if the model is manipulated |
| −2 | publisher verification (unlinked) — no provenance/repo link, but the shipped source was fully read |
Capability observations and info notes are shown under Findings but never scored.
Open any row's finding below for the file, line and evidence behind a deduction.
Findings 9
high Dynamic evaluation of a non-literal value (dist/tools/advanced/content-script-eval.js)MTC-SRC-010
In the server's implementation (`dist/tools/advanced/content-script-eval.js:22`): Evaluating a runtime value as code (rather than a fixed literal) executes whatever reaches it — a direct RCE primitive, and almost never necessary in legitimate code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: return JSON.stringify(eval(expr)); } catch (e) { return JSON.stringify({ error
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/tools/advanced/content-script-eval.js
high Tool "eval_service_worker" exposes command/code executionMTC-CAP-001
Tool "eval_service_worker" appears to run shell commands or evaluate code (keyword "eval" in tool name). Arbitrary execution driven by model input is one of the most dangerous MCP capabilities; combined with any untrusted input it becomes RCE.
Fix: Sandbox execution, allowlist commands/arguments, and never pass model output to a shell unescaped.
Location: tool eval_service_worker
high Tool "eval_extension_page" exposes command/code executionMTC-CAP-001
Tool "eval_extension_page" appears to run shell commands or evaluate code (keyword "eval" in tool name). Arbitrary execution driven by model input is one of the most dangerous MCP capabilities; combined with any untrusted input it becomes RCE.
Fix: Sandbox execution, allowlist commands/arguments, and never pass model output to a shell unescaped.
Location: tool eval_extension_page
high Tool "content_script_eval" exposes command/code executionMTC-CAP-001
Tool "content_script_eval" appears to run shell commands or evaluate code (keyword "eval" in tool name). Arbitrary execution driven by model input is one of the most dangerous MCP capabilities; combined with any untrusted input it becomes RCE.
Fix: Sandbox execution, allowlist commands/arguments, and never pass model output to a shell unescaped.
Location: tool content_script_eval
high Dynamic code execution in server code (dist/tools/advanced/content-script-eval.js)MTC-SRC-001
In the server's implementation (`dist/tools/advanced/content-script-eval.js:22`): Evaluating strings as code is the most direct RCE primitive; if any tool input reaches it, the server executes attacker-chosen code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: return JSON.stringify(eval(expr)); } catch (e) { return JSON.stringify({ error
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/tools/advanced/content-script-eval.js
high Dynamic code execution in server code (dist/tools/extension/eval-extension-page.js)MTC-SRC-001
In the server's implementation (`dist/tools/extension/eval-extension-page.js:12`): Evaluating strings as code is the most direct RCE primitive; if any tool input reaches it, the server executes attacker-chosen code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: const fn = new Function('return (async () => { ' + expr + ' })()'); const res = await fn();
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/tools/extension/eval-extension-page.js
low Mutating tool "eval_service_worker" declares no destructiveHintMTC-CAP-005
Tool "eval_service_worker" can mutate/egress but declares no destructiveHint. Clients that don't default to spec-safe behavior may not prompt before running it.
Fix: Declare accurate annotations, and gate destructive tools on user confirmation regardless.
Location: tool eval_service_worker
low Mutating tool "eval_extension_page" declares no destructiveHintMTC-CAP-005
Tool "eval_extension_page" can mutate/egress but declares no destructiveHint. Clients that don't default to spec-safe behavior may not prompt before running it.
Fix: Declare accurate annotations, and gate destructive tools on user confirmation regardless.
Location: tool eval_extension_page
low Mutating tool "content_script_eval" declares no destructiveHintMTC-CAP-005
Tool "content_script_eval" can mutate/egress but declares no destructiveHint. Clients that don't default to spec-safe behavior may not prompt before running it.
Fix: Declare accurate annotations, and gate destructive tools on user confirmation regardless.
Location: tool content_script_eval
Tools 23
Each tool and what it can reach — statically extracted from the published source.
content_script_evalruns code / shelleval_extension_pageruns code / shelleval_service_workerruns code / shellsend_messagenetwork egressclickno sensitive capabilityconsole_logsno sensitive capabilitydnr_matched_rulesno sensitive capabilitydnr_rulesno sensitive capabilityextension_errorsno sensitive capabilityextension_loadno sensitive capability
Show 13 more tools ↓
manifest_validateno sensitive capabilitynavigateno sensitive capabilitynetwork_requestsno sensitive capabilityopen_popupno sensitive capabilityopen_sidepanelno sensitive capabilitypermissions_checkno sensitive capabilityreload_extensionno sensitive capabilityscreenshotno sensitive capabilitysnapshotno sensitive capabilitystorage_getno sensitive capabilitystorage_setno sensitive capabilitytypeno sensitive capabilitywait_forno sensitive capability
What this scan could not see
- Tools were statically extracted from the published source (23 recovered), not enumerated from a running server. Tool-poisoning, Unicode-smuggling, capability and toxic-flow analysis ran on this inferred surface, but a mis-parsed registration could be missed or mis-attributed, so tool-derived findings are capped below “confirmed”. To grade the real runtime surface, scan the running server: --command "npx -y <package>".
Versions 1
Scan history per published version. The engine is deterministic — the same version always yields the same score, so a changed score means the package itself changed.
| Version | Score | Findings | Engine | Scanned |
|---|---|---|---|---|
v0.3.1 latest |
A 92/100 | 9 | 1.9.0 | 2026-07-24 |
Embed this score
Show this server's live Trust Score in your README, docs or website. The badge is served straight from the registry and updates automatically after every rescan — no API key needed. It links back to this page, so anyone who sees the grade can also read the findings behind it instead of taking a number on faith.
Verify this score yourself
The score above is reproducible: the same package version always yields the same result. Run it locally or over the free API — no account, no LLM, fully deterministic.
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