From 441db376848e3bd19448b3d51649a37a12ff5dff Mon Sep 17 00:00:00 2001
From: Alejandro Romero Herrera <alromh87@gmail.com>
Date: Mon, 21 Sep 2020 12:56:18 +0300
Subject: [PATCH 1/2] Fix Arbitary Code Execution

---
 index.js | 42 ++++++++++++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 8 deletions(-)

diff --git a/index.js b/index.js
index 6038599..77831f6 100644
--- a/index.js
+++ b/index.js
@@ -2,7 +2,7 @@
 
 var fs		= require('fs');
 var http	= require('http');
-var exec	= require('child_process').exec;
+var execFile	= require('child_process').execFile;
 
 var serialNumber = function (cb, cmdPrefix) {
 	var delimiter = ': ';
@@ -45,6 +45,32 @@ var serialNumber = function (cb, cmdPrefix) {
 		return result;
 	};
 
+	var filterOutput = function (input, search) {
+		var result = [];
+		input = input.split('\n').filter(i => i);
+		input.forEach( line => {
+			if(line.includes(search))result.push(line);
+		});
+		return result.join('\n');
+	};
+
+	var execCmd = function (cmdPrefix, cmd, val, callback) {
+		if (cmdPrefix.endsWith(' ')) {	// If ends with space is treated as a comand, like sudo
+			var cmdArgs = cmd;
+			cmd = cmdPrefix.trim();
+		} else {							// Else path, apend
+			var cmdArgs = cmd.slice(1);
+			cmd = cmdPrefix + cmd[0];
+		}
+		if (process.platform == 'win32') {
+			args.push(val);
+		}
+		execFile(cmd, cmdArgs, (error, stdout) => {
+			if(process.platform != 'win32') stdout = filterOutput(stdout, val);
+			if(callback) callback(error, stdout);
+		});
+	}
+
 	var attemptEC2 = function (failCb) {
 		var data = '';
 		var failHandler = function () {
@@ -77,25 +103,25 @@ var serialNumber = function (cb, cmdPrefix) {
 	case 'win32':
 		delimiter = '\r\n';
 		vals[0] = 'IdentifyingNumber';
-		cmd = 'wmic csproduct get ';
+		cmd = ['wmic', 'csproduct', 'get'];
 		break;
 
 	case 'darwin':
-		cmd = 'system_profiler SPHardwareDataType | grep ';
+		cmd = ['system_profiler', 'SPHardwareDataType'];
 		break;
 
 	case 'linux':
 		if (process.arch === 'arm') {
 			vals[1] = 'Serial';
-			cmd = 'cat /proc/cpuinfo | grep ';
+			cmd = ['cat', '/proc/cpuinfo'];
 
 		} else {
-			cmd = 'dmidecode -t system | grep ';
+			cmd = ['dmidecode', '-t', 'system'];
 		}
 		break;
 
 	case 'freebsd':
-		cmd = 'dmidecode -t system | grep ';
+		cmd = ['dmidecode', '-t', 'system'];
 		break;
 	}
 
@@ -103,11 +129,11 @@ var serialNumber = function (cb, cmdPrefix) {
 
 	if (serialNumber.preferUUID) vals.reverse();
 
-	exec(cmdPrefix + cmd + vals[0], function (error, stdout) {
+	execCmd(cmdPrefix, cmd, vals[0], (error, stdout) => {
 		if (error || parseResult(stdout).length > 1) {
 			stdoutHandler(error, stdout);
 		} else {
-			exec(cmdPrefix + cmd + vals[1], stdoutHandler);
+			execCmd(cmdPrefix, cmd, vals[1], stdoutHandler);
 		}
 	});
 };

From a6f0dd1d9d5927f0ba5bc5386276e6afb44a1a6d Mon Sep 17 00:00:00 2001
From: Alejandro Romero Herrera <alromh87@gmail.com>
Date: Fri, 9 Oct 2020 16:39:57 +0300
Subject: [PATCH 2/2] Updated to use spawn on non win systems

---
 index.js | 47 ++++++++++++++++++++++++++++++++++-------------
 1 file changed, 34 insertions(+), 13 deletions(-)

diff --git a/index.js b/index.js
index 77831f6..b012e4d 100644
--- a/index.js
+++ b/index.js
@@ -3,6 +3,7 @@
 var fs		= require('fs');
 var http	= require('http');
 var execFile	= require('child_process').execFile;
+var spawn	= require('child_process').spawn;
 
 var serialNumber = function (cb, cmdPrefix) {
 	var delimiter = ': ';
@@ -45,15 +46,6 @@ var serialNumber = function (cb, cmdPrefix) {
 		return result;
 	};
 
-	var filterOutput = function (input, search) {
-		var result = [];
-		input = input.split('\n').filter(i => i);
-		input.forEach( line => {
-			if(line.includes(search))result.push(line);
-		});
-		return result.join('\n');
-	};
-
 	var execCmd = function (cmdPrefix, cmd, val, callback) {
 		if (cmdPrefix.endsWith(' ')) {	// If ends with space is treated as a comand, like sudo
 			var cmdArgs = cmd;
@@ -64,11 +56,40 @@ var serialNumber = function (cb, cmdPrefix) {
 		}
 		if (process.platform == 'win32') {
 			args.push(val);
+			execFile(cmd, cmdArgs, (error, stdout) => {
+				if(callback) callback(error, stdout);
+			});
+		} else { // If not win32 use spawn for grep
+			let stdout = '';
+			let stderr = '';
+			const spCmd1 = spawn(cmd, cmdArgs);
+			const spCmd2 = spawn('grep', [val]);
+
+			spCmd1.stdout.on('data', (data) => {
+				spCmd2.stdin.write(data);
+			});
+			spCmd1.stderr.on('data', (data) => {
+				stderr += data;
+			});
+			spCmd1.on('close', (code) => {
+				if (code !== 0) {
+					console.error(`${cmd1} process exited with code ${code}`);
+				}
+				spCmd2.stdin.end();
+			});
+			spCmd2.stdout.on('data', (data) => {
+				stdout += data.toString();
+			});
+			spCmd2.stderr.on('data', (data) => {
+				stderr+= data;
+			});
+			spCmd2.on('close', (code) => {
+			if (code !== 0) {
+				console.error(`${cmd2} process exited with code ${code}`);
+			}
+				if(callback) callback(stderr, stdout);
+  			});
 		}
-		execFile(cmd, cmdArgs, (error, stdout) => {
-			if(process.platform != 'win32') stdout = filterOutput(stdout, val);
-			if(callback) callback(error, stdout);
-		});
 	}
 
 	var attemptEC2 = function (failCb) {