I am trying to run a .bat file from my Java application, but I am worried about the command line injection or any other possible attacks that might arise if I run a .bat using a Java application. Is there a secure way that to run a .bat file using a Java application?
>Solution :
Well the short answer is to clean the input being sent to the batch script. Effectively this means the command line parameters. For example,
Process p = Runtime.getRuntime().exec("runBatch.bat")
If you don’t pass anything to the batch file that is entirely safe because there is nothing the user could manipulate that would make you do something you didn’t intend. This is assuming the hacker can’t swap out the batch script you run, but that’s attacking something else in your environment other than your Java software (ie OS, file shares, file permissions, etc).
This all depends on what command line parameters you are sending to the batch script.
Process p = Runtime.getRuntime().exec(new String[] { "runBatch.bat", arg1, arg2 });
If arg1 and arg2 could be populated from user input then you’ll need to clean them. Mostly, I’d be keen to focus of any file paths they could try and mess with. For example, if you wanted to have them provide information about certain file paths, but that file path shouldn’t escape a root directory then you need to contain the resulting path to that directory.
File rootDir = new File("...")
File arg1 = new File( userInput )
File arg2 = new File( userInput )
if( isWithin( rootDir, arg1 ) && isWithin( rootDir, arg2 ) ) {
Runtime.getRuntime().exec( new String[] { "runBatch.bat", arg1, arg2 } )
}
public boolean isWithn( File rootDir, File file ) {
return arg1. getCanonicalPath().startsWith( rootDir. getCanonicalPath() );
}
Beyond that you just need to sanity check other parameters to make sure they are what you expect.