I've recently gone into a serious security problem in my Java app. The client application simply works on a FTP and MySQL server, and access information to both of them are stored directly in code. I'm aware that it's an awfull idea and I'm planning to move that informations to a preferences file. But how can it help to raise a security level on my app? Is there any way to properly secure such file? Or should I look for a different solution?
Keep passwords in a keystore (example: http://kingsfleet.blogspot.com/2008/12/storing-password-somewhere-safe.html). Keystore has to be protected with a password, so in order to use client application user needs to give keystore password - I am not sure if this is acceptable in your case.
Related
Currently i am dealing with a conceptional issue in my Java - SFTP Client/Server - Setup.
Basically i got a client who sends files to a remote server and stores them there. BUT: You trigger the upload via a jar file on your computer, so anyone could decrypt the jar file and read the clear java file and obtain the credentials for my sftp.
Is there any technology to solve this issue or some workaround you can advise?
Greetings and Thanks!
It is inadvisable to put credentials into a common / shared JAR file. It can't be done securely, and if you need to get the user to replace them they need to download and install a new JAR.
There is no way that you can keep the credentials private from the user. If your credentials need to be used on the user's machine, then it will be possible for the user to extract them, somehow. No matter what you try. (Assuming that they control their machine ....)
Saving credentials encrypted does not protect them from the user. The application needs the decryption key. The user can find / extract that and then recover the credentials.
It is better to issue distinct upload credentials for each user. That way, if one user loses or abuses his credentials you can invalidate them without affecting other users.
If I'm understanding your issue correctly, it is rooted at the fact that your java sources contain your credentials.
First, I highly recommend using jSch library for a great implementation of SSH2.
Regarding your credentials, you can find your answer here.
In short - save your credentials encrypted.
I'm trying to learn how to send an email using a Netbeans application. Whenever I run the application, I keep getting the following error:
javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted.
I got code from two different sources (specified below) and both give the exact same error. I used the correct .jar files, and the code was copied exactly as shown in the tutorials, but neither works. I also tried using my proper Gmail credentials (made sure they were 100% correct) and I still get the error.
What I want to know is:
What do I use as username and password? (are there predefined ones I need to obtain or do I need to create them, and if so how?)
Sources:
This one does not specify a password anywhere at all: Email: How to send email using java Netbeans [Tutorial] - YouTube
This one specifies a password as String pass = "****"; which I changed to String pass = "pass123";: Send email using Java (in NetBeans)
Okay I found out the answer. The thing that was causing the error was:
Gmail actually prevented the application from sending the email from the Java application because it read it as a "Less secure app" trying to sign in to my account.
A few relevant changes and the application works now
I hope you have downloaded the required jars to fulfill Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files.
Now when you want to connect with Gmail account programmatically then you have to enable the allow less secure apps. You can do that by using the following link.
If you access more times repeatedly then the access can be blocked by Google and even Google will intimate with Critical Security Alerts
Allow Less secured Apps
I'm looking for a way to open a JDBC connection without specifying my database login and password in plain text, as the application will be distributed and any Java decompiler would reveal them, allowing the users to access the database easily.
Is there any way to encrypt them, or store them somewhere else?
Looks like you want to let Android application talk to your database directly? Don't do that. It's a major security flaw. No matter how you encrypt your credential, you have to reveal your plain text somewhere during the execution of the program, and anyone with a debugger can see that. The correct way is to have use an API on your web service and call that API from client. All database transaction should happen in a trusted intranet.
Why would you want to do this? Generally the business side of your application would have this info and connect to MySQL. There, a user does not have access to any code. Then you create an endpoint that actually is accessible to the public. There you can worry about passing username and password stuff to the business logic, which again, actually has direct access to your database.
Basically, do not open a jdbc connection anywhere but your server side. Its a security measure.
Problem Description
I am writing application for Android. Application must do following:
Connect to the server using following URL:
http://www.example.com/database.xml?username=xxx&password=xxx
username and password I must keep in the phone and this username and password are same for the all users. For example if 1.000.000 people have my application they all connect to the server using same url same username and password.
Download database.xml file from URL and save data in the SQLite database.
Issues
How I can use URL in my application to be sure that users which have access to my codes can't know from the code which URL I use and also to keep secure my password and username.
Or even just to keep whole URL secure http://www.example.com/database.xml?username=xxx&password=xxx as it is same for all users.
How I can protect my SQLite database. For example if somebody has root access on the phone he can get database open it and get all information which I keep there.
I need to protect my data.
I think you should go for ProGuard. I know its very hard to prevent from reverse-engineering. Following are some post which give some knowledge about this.
How to avoid reverse engineering of an APK file?
Is it really impossible to protect Android apps from reverse engineering?
Protecting Your Android Applications is an article which describes necessary information about ProGuard.
Read FAQ to know more.
To protect database, use SQLCipher.
use HttpRequest apis to get the data instead of using browser intent.
In your case I don't see any perfect protection engineering. Any one with a primary reverse engineering knowledge can get the data from your code.
I have a plain Java application which is supposed to connect to the database. I don't want to store database connection url and username/password in a properties file or hardcode it in application. What is a common way to solve this problem? How a Java application can connect to database without revealing username/password?
I'm a .NET dev, but I've run into the exact same situation.
Last year I was working at a company that had to be PCI compliant to store credit card data, so security was a big deal. The URL/login data has to exist somewhere. The most common method I've seen for securing it is with encryption. I don't know about Java in particular, but .NET has several encryption namespaces in the core Framework. We used these to encrypt the database logins.
You still have a potential security vulnerability, which are the encryption keys used to encrypt/decrypt the data. We used the PCI "compensating controls" method here. Access to the keys is restricted to "key management" role. We also tracked access of the key itself so that there was a record of all user-initiated and system-initiated access. No one user had access to these logs, so there could be no covering of tracks by a single user. These overlapping security methods essentially create a situation where nothing less than a coordiated conspiracy between multiple administrators is required to put the data in jeopardy.
If you aren't willing to store it, you have to prompt for it. You could encrypt the password, but then you have to have a key to decrypt it and you are stuck in the same problem.
One of the common solutions to this problem for server based applications is to store the username and password in a file that has user permissions set in such a way that only the executing user of the application/service can read its contents.
For example, you run your application as user foo-service and it inherits all of the access privileges of the foo-service user. The file containing the username and password is only readable by that user. You read the value from the file and connect to the database as normal.
Possible problems with this approach:
The superuser of this machine may be able to get the password to the database.
An attacker who has penetrated your application security can get access to the database credentials.
The above problems are normally mitigated by tuning the access privileges for the application to the database and the network. Nearly any other solution you come up will get you into a chicken-and-egg problem because you are basically trying to hide something from itself.
The best way would be to store the information as a configured data source in the JNDI context of your application server. You can then use the facilities of the application server to configure data sources at deployment time. All the application has to do is look up the appropriate JNDI name at runtime and use that. This is a common pattern for Java web applications.
Use web services to separate your application from the server doing the database access. Sign your web application and then only allow a properly signed application to call the web services server.
You can try to load a file using system properties.
-Dapplication.configuration=application.properties.
When the property file is not passed then the you should use default file with default config.
When the file exists you override the defaults with the values provided from configuration.
java -Dlog4j.configuration=file:/log4j.properties -Dapplication.configuration=file:/live-conf.conf -jar app.jar "applicationarg1" "applicationarg1"
More sources to follow:
https://docs.oracle.com/javase/tutorial/essential/environment/properties.html
How to override system properties:
-Dproperty=value
Set a system property value. If value is a string that contains spaces, you must enclose the string in double quotes:
http://docs.oracle.com/javase/6/docs/technotes/tools/windows/java.html