registry / @onyxsecurity/mcp-gateway / 1.0.116

@onyxsecurity/mcp-gateway@1.0.116

A TypeScript SSE proxy for MCP servers that use stdio transport.

Static Scan Results

scanned 14d ago · by rust-scanner

Static analysis flagged 15 finding(s) at 72.0% confidence. This version is warn-only unless an AI or security-team review confirms malicious behavior.

Static reason

One or more suspicious static signals were detected.

Decision evidence

public snapshot

Behavioral surface

Source

ChildProcessDynamicRequireEnvironmentVarsFilesystemNativeBindingsNetwork

Supply chain

HighEntropyStringsMinifiedObfuscatedUrlStrings

Manifest

NoLicense

scanned 18 file(s), 787 KB of source, external domains: example.com, github.com

Source & flagged code

5 flagged

dist/main-CpwH4w9e.jsView file

Lines 1-6javascript

1import{AccessControlBlockError as e,Client as t,ConfigurationError as n,ProxyConnectionError as r,ReadBuffer as i,Server as a,StdioServerTransport as o,compressClientInfo as s,getSessionData as c,initializeTrafficMirror as l,logRequestCounts as u,proxyServer as d,redactCliArgs as f,serializeMessage as p,startHTTPServer as m}from"./stdio-CwWRc8TT.js";import{UnauthorizedError as ee,createParser as h,normalizeUrl as g}from"./normalizeUrl-fkFv5Mfb.js";import{config as _}from"./env-IMxXxvN0.js";import{chownToRealUser as v,extractTraceIdFromHeaders as te,flushLogs as y,logger as b}from"./logger-4h11 ...

2`);this.buffer=r.pop()||``;let i=[];for(let e of r)e.trim().startsWith(`{`)?i.push(e):e.trim().length>0&&this.logDroppedLine(e);if(i.length>0){let e=`${i.join(`

High

Child Process

Package source references child process execution.

dist/main-CpwH4w9e.jsView on unpkg · L1

High

Command Output Exfiltration

Source combines command execution, command-output handling, and outbound requests; review data flow before blocking.

dist/main-CpwH4w9e.jsView on unpkg · L1

3`)}\n`;n(null,Buffer.from(e))}else n(null,null)}logDroppedLine(e){if(!(this.droppedLinesLogged>50)){if(this.droppedLinesLogged===50){this.droppedLinesLogged+=1,b.info(`Suppressing further non-JSON stdout lines`,{eventType:`mcp_server_stdout_dropped_suppressed`,loggedSoFar:50});return}this.droppedLinesLogged+=1,b.info(`MCP server stdout (non-JSON, dropped)`,{eventType:`mcp_server_stdout_dropped`,line:e.length>1024?`${e.slice(0,1024)}…`:e})}}},ze=class{onclose;onerror;onmessage;get pid(){return this._process?.pid??null}get stderr(){return this._stderrStream?this._stderrStream:this._process?.stde ...

4`);return Ge({exitCode:1,logMessage:`MCP server blocked by access control policy`,meta:{error:t.message,eventType:`mcp_access_control_block`,reason:t.reason},reason:e,respondToClient:a,stderrLine:n})}let l=c(t instanceof n?`Onyx MCP gateway: configuration error — ${t.message}`:t instanceof r?`Onyx MCP gateway: cannot reach the upstream MCP server${o?` at ${o}`:``} — ${t.message}`:`Onyx MCP gateway: failed to start — ${t

5`);c=t.pop()??``;for(let e of t){if(e.length===0)continue;u(e)}c.length>8192&&d()}),n.stderr?.once(`end`,m),n.stderr?.once(`close`,m);try{return await t.connect(n),t}catch(e){throw m(),b.warn(`Failed original server access`,{command:h,error:e instanceof Error?e.message:String(e),eventType:`mcp_server_access_failed`,proxyType:s,stderrTail:l.slice(-20)}),new r(`Failed to connect to stdio process: ${e}`,void 0,`stdio`,{argCount:v?.length,command:h})}}else if(s===`remote`){let e=S,t=()=>{let e={...w};return Object.keys(e).length>0?{headers:e}:void 0},n=e=>{if(e instanceof ee)return!0;if(e&&typeof ...

6//# sourceMappingURL=main-CpwH4w9e.js.map

Long lines were clipped for display.

dist/helpers-BPQVbZuN.jsView file

Lines 1-21javascript

Source & flagged code

5 flagged · loading source

dist/main-CpwH4w9e.jsView file

High

Child Process

Package source references child process execution.

dist/main-CpwH4w9e.jsView on unpkg · L1

1import{AccessControlBlockError as e,Client as t,ConfigurationError as n,ProxyConnectionError as r,ReadBuffer as i,Server as a,StdioServerTransport as o,compressClientInfo as s,getS... L2: `);this.buffer=r.pop()||``;let i=[];for(let e of r)e.trim().startsWith(`{`)?i.push(e):e.trim().length>0&&this.logDroppedLine(e);if(i.length>0){let e=`${i.join(` L3: `)}\n`;n(null,Buffer.from(e))}else n(null,null)}logDroppedLine(e){if(!(this.droppedLinesLogged>50)){if(this.droppedLinesLogged===50){this.droppedLinesLogged+=1,b.info(`Suppressing ... L4: `);return Ge({exitCode:1,logMessage:`MCP server blocked by access control policy`,meta:{error:t.message,eventType:`mcp_access_control_block`,reason:t.reason},reason:e,respondToClie...

High

Same File Env Network Execution

A single source file combines environment access, network access, and code or shell execution; review context before blocking.

dist/main-CpwH4w9e.jsView on unpkg · L1

High

Command Output Exfiltration

Source combines command execution, command-output handling, and outbound requests; review data flow before blocking.

dist/main-CpwH4w9e.jsView on unpkg · L1

dist/helpers-BPQVbZuN.jsView file

Medium

Dynamic Require

Package source references dynamic require/import behavior.

dist/helpers-BPQVbZuN.jsView on unpkg · L1

1import{__commonJSMin as e,__toESM as t}from"./chunk-CrDKVgUD.js";import{createRequire as n}from"node:module";import{readFileSync as r,readdirSync as i}from"node:fs";import{format a... L2: `).map(e=>e.split(` `)),n=0;return t.forEach(e=>{e.length>1&&C.stringWidth(e[0])>n&&(n=Math.min(Math.floor(this.width*.5),C.stringWidth(e[0])))}),t.forEach(e=>{this.div(...e.map((t... ... L4: `):e.text.split(` L5: `),e.border&&(r.unshift(`.`+`-`.repeat(this.negatePadding(e)+2)+`.`),r.push(`'`+`-`.repeat(this.negatePadding(e)+2)+`'`)),e.padding&&(r.unshift(...Array(e.padding[0]||0).fill(``)),... L6: `),l=[...c],u=0;for(let[e,t]of l.entries()){if(r+=t,Me.has(t)){let{groups:e}=RegExp(`(?:\\[(?<code>\\d+)m|\\${Ne}(?<uri>.*))`).exec(c.slice(u))||{groups:{}};if(e.code!==void 0){le... ... L29: */ L30: var D;(function(e){e.BOOLEAN=`boolean`,e.STRING=`string`,e.NUMBER=`number`,e.ARRAY=`array`})(D||={});let O;var qe=class{constructor(e){O=e}parse(e,t){let n=Object.assign({alias:voi... L31: `);b.div(`${e}\n`)}return b.toString().replace(/\s*$/,``)};function _(e,n,r){let i=0;return Array.isArray(e)||(e=Object.values(e).map(e=>[e])),e.forEach(e=>{i=Math.max(t.stringWidt... ... L35: # L36: # Installation:

Medium

Install Persistence

Source writes installer persistence such as shell profile or service configuration.

dist/helpers-BPQVbZuN.jsView on unpkg · L1

Findings

3 High5 Medium7 Low

HighChild Processdist/main-CpwH4w9e.js

HighSame File Env Network Executiondist/main-CpwH4w9e.js

HighCommand Output Exfiltrationdist/main-CpwH4w9e.js

MediumDynamic Requiredist/helpers-BPQVbZuN.js

MediumNetwork

MediumEnvironment Vars

MediumInstall Persistencedist/helpers-BPQVbZuN.js

MediumStructural Risk Force Deep Review

LowNon Install Lifecycle Scripts

LowScripts Present

LowFilesystem

LowObfuscated

LowHigh Entropy Strings

LowUrl Strings

LowNo License

Source & flagged code

5 flagged

dist/main-CpwH4w9e.jsView file

Lines 1-6javascript

2`);this.buffer=r.pop()||``;let i=[];for(let e of r)e.trim().startsWith(`{`)?i.push(e):e.trim().length>0&&this.logDroppedLine(e);if(i.length>0){let e=`${i.join(`

High

Child Process

Package source references child process execution.

dist/main-CpwH4w9e.jsView on unpkg · L1

High

Command Output Exfiltration

Source combines command execution, command-output handling, and outbound requests; review data flow before blocking.

dist/main-CpwH4w9e.jsView on unpkg · L1

6//# sourceMappingURL=main-CpwH4w9e.js.map

Long lines were clipped for display.

dist/helpers-BPQVbZuN.jsView file

Lines 1-21javascript