Fix a vulnerability from a crafted argument to 'bunyan -p ARG'

This was reported privately as:
    https://hackerone.com/reports/902739
    bunyan - RCE via insecure command formatting

After this change:
    % ./bin/bunyan -p "S'11;touch hacked ;'\\"
    bunyan: error: no matching PIDs found for "S'11;touch hacked ;'\"

With _DEBUG self-logging to show the escaped command:
    % ./bin/bunyan -p "S'11;touch hacked ;'\\"
    (bunyan: exec cmd: "ps -A -o pid,command | grep '[S]'\\''11;touch hacked ;'\\''\\\\'")
    bunyan: error: no matching PIDs found for "S'11;touch hacked ;'\"
    (bunyan: cleanupAndExit)
    (bunyan: process.exit(2))

Before this change these would create a "hacked" file in the current dir.

CHANGES.md

@@ -10,6 +10,18 @@ Known issues:
 (nothing yet)
 
 
+## 1.8.13
+
+- Fix a vulnerability from a crafted argument to 'bunyan -p ARG'
+
+  This was reported privately as:
+      https://hackerone.com/reports/902739
+      bunyan - RCE via insecure command formatting
+
+  Previous to this version the 'bunyan' CLI was not escaping a given argument
+  to the '-p' option before executing `ps -A -o pid,command | grep '$ARG'`
+  which could lead to unintended execution.
+
 ## 1.8.12
 
 - [issue #444] Fix the `bunyan` CLI to not duplicate the "HTTP/1.1 ..." status

bin/bunyan

@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 /**
- * Copyright 2017 Trent Mick
- * Copyright 2017 Joyent Inc.
+ * Copyright 2020 Trent Mick
+ * Copyright 2020 Joyent Inc.
  *
  * bunyan -- filter and pretty-print Bunyan log files (line-delimited JSON)
  *
@@ -11,7 +11,7 @@
  * vim: expandtab:ts=4:sw=4
  */
 
-var VERSION = '1.8.12';
+var VERSION = '1.8.13';
 
 var p = console.log;
 var util = require('util');
@@ -1266,7 +1266,15 @@ function processPids(opts, stylize, callback) {
                 // own search.
                 regex = '[' + regex[0] + ']' + regex.slice(1);
             }
-            exec(format('ps -A -o pid,command | grep \'%s\'', regex),
+            var cmd = format('ps -A -o pid,command | grep \'%s\'',
+                // Escape single-quotes to avoid breaking the grep arg quoting
+                // (leading to a possible *code execution*) and backslashes to
+                // avoid undoing that escaping.
+                regex.replace(/\\/g, '\\\\')
+                    // JSSTYLED
+                    .replace(/'/g, "'\\''"));
+            if (_DEBUG) { warn('(bunyan: exec cmd: %j)', cmd); }
+            exec(cmd,
                 function (pidsErr, stdout, stderr) {
                     if (pidsErr) {
                         warn('bunyan: error getting PIDs for "%s": %s\n%s\n%s',

lib/bunyan.js

@@ -8,7 +8,7 @@
  * vim: expandtab:ts=4:sw=4
  */
 
-var VERSION = '1.8.12';
+var VERSION = '1.8.13';
 
 /*
  * Bunyan log format version. This becomes the 'v' field on all log records.

package.json

@@ -1,21 +1,27 @@
 {
   "name": "bunyan",
-  "version": "1.8.12",
+  "version": "1.8.13",
   "description": "a JSON logging library for node.js services",
   "author": "Trent Mick <trentm@gmail.com> (http://trentm.com)",
   "main": "./lib/bunyan.js",
   "bin": {
     "bunyan": "./bin/bunyan"
   },
-
   "repository": {
     "type": "git",
     "url": "git://github.com/trentm/node-bunyan.git"
   },
-  "engines": ["node >=0.10.0"],
-  "keywords": ["log", "logging", "log4j", "json", "bunyan"],
+  "engines": [
+    "node >=0.10.0"
+  ],
+  "keywords": [
+    "log",
+    "logging",
+    "log4j",
+    "json",
+    "bunyan"
+  ],
   "license": "MIT",
-
   "// dtrace-provider": "required for dtrace features",
   "// mv": "required for RotatingFileStream",
   "// moment": "required for local time with CLI",
@@ -32,10 +38,8 @@
     "verror": "1.3.3",
     "vasync": "1.4.3"
   },
-
   "scripts": {
     "test": "make test"
   },
-  "dependencies": {
-  }
+  "dependencies": {}
 }