Wednesday, April 29, 2015

Antitamper Mobile - Minded Security's Magik Quadrant for Mobile Code Protection


Minded Security's Magik Quadrant for Mobile Code Protection shows you our evaluation of the top vendors in this market, based on our research and experience.

Magik Quadrant



Why care about Code Protection?

There are a lot of reasons to care about Code Protection when dealing with Mobile Applications.
Every year a lot of money is lost due to piracy, intellectual property theft, cracked copyright mechanisms, tampered software, malware, and so on.
Mobile Apps are obviously installed client-side, therefore they are under the user's control.
For example, malicious users or competitors could decompile the application and analyse the result.
This could reveal valuable data as proprietary algorithms or intellectual property or allow the attackers to use that information to modify the code, repackage and redistribute it to create a "trojanized" clone of the App in a rapid fashion.
Moreover, if the App needs to run on untrusted devices, any malware could interact with the App at runtime level to steal data (credentials, credit card number etc.) or bypass security logic (local authentication, geo-restrictions, custom cryptography etc.).
As you can see a mobile App could be attacked at various layers and with very different goals in mind, creating a very complex problem for those who want to protect their products.
The following diagram shows some of the main attack types.

Why Apps reverse-engineering and tampering are easy?

Many developers do not know how easy mobile application reverse-engineering and tampering are. 
Since mobile Apps reside on user's devices and include valuable data inside  -  metadata, resources and even the code itself -, attackers could gather important information just by using publicly available tools.
In fact, according to the OWASP Top 10 Mobile Risks 2014,
“...it is extremely common for apps to be deployed without binary protection. The prevalence has been studied by a large number of security vendors, analysts and researchers.”

Without protections, it is quite easy to decompile an App to analyse its code (particularly on the Android platform) or to interact with it at runtime level on rooted/jailbroken devices.

How to make it harder?

To make the life harder to the attackers and help protecting valuable data, developers should:
  • Harden DRM systems and licensing modules
  • Reduce piracy
  • Protect intellectual property and personal data
  • Secure proprietary algorithms against analysis and reverse engineering
  • Harden firmware and OS
  • Protect cryptographic keys
  • Protect the client side of encrypted communication
  • Prevent malware intrusion
Therefore they have to deploy mobile applications with some kind of protection. To do this they could implement the following techniques:
  • Code and Flow Obfuscation
  • String and Class Encryption
  • Debug code stripping
  • Method Call Hiding (Reflection)
  • Resource Encryption
  • Debug Detection
  • Root/Jailbreak Detection
  • Runtime Injection Detection (Swizzle/Hook Detection)
  • Tamper Detection
  • Certificate Pinning
  • Watermarking
There are many technical resources on Internet that describe at some level of detail how to implement one or more of the preceding techniques.
Moreover, there is some commercial tool which provides binary protection without requiring developers to implement their own custom controls.
Before going into detail about these tools it is worth noting that all these security controls do not give a guarantee that mobile applications are going to be 100% secure, but they can provide additional protection and make very hard to carry on reverse engineering, tampering and runtime attacks.

Interpreting the Magik Quadrant

The Magik Quadrant study performed on Code Protection solutions takes into account multiple criteria based on:
  • Ability to Execute
  • Completeness of Vision

Ability to Execute

Vendors must deliver strong functionality in the following areas of capability:
  • Techniques implemented 
  • After Sale Support

Completeness of Vision

Completeness of vision in the Code Protection market considers a vendor’s vision and plans for addressing buyer needs in the future.
  • Cross-platform support
  • Innovation
  • Sale Strategy
Before proceeding it is worth noting that focusing on the leaders' quadrant isn't always the best choice. There are good reasons to consider market challengers. Moreover a niche player may support a specific needs better than a market leader.

Leaders

Leaders offer products and services that best cover current scenarios and are well positioned for tomorrow. They provide solutions that are cross-platform, and therefore with one vendor it is possible to protect many platforms.
Their complex solutions provide protection (through obfuscation, encryption, call hiding etc.), detection and reaction (in case an attack is detected).

Visionaries

In general, in any Magic Quadrant the Visionaries are the innovators. They understand well where the market is going and therefore they can provide innovative techniques to protect Apps in a cross-platform environment.

Niche Players

Niche Players, in our research, are vendors that do not offer, at the moment, a cross-platform solution but they are focused on a small segment.
Since they are offering platform-specific solutions, in some case they are able to provide innovative and specific solutions for that particular target.

Free and Open Source Solutions

The preceding analysis was done on commercial tools available on market.
In addition to this, we have also analyzed a free and open source solutions available for iOS: iMAS.
This solution has the main disadvantage that, since it is free and open source, it does not guarantee support. Nevertheless, we want to spend some words about it since it has some interesting features.

Vendor Strengths and Cautions

Arxan

This analysis pertains to Arxan's GuardIT.
Arxan is one of the most trusted names in application security. They provide protection against a widest range of static and dynamic attacks. The protection, provided by GuardIT, is implemented on different layers giving  the chance to select the desired level of security.

Strengths
  • Cross-platform (Android, iOS, Windos Phone)
  • Strong code protection
  • Strong detection
  • Capability to repair after damage

Cautions
  • Price could be higher than expected

Company website: www.arxan.com

Metaforic

This analysis pertains to Metaforic Core, Authenticator, Concealer and WhiteBox.
Metaforic is one of the leaders in the application security market. They provide a cross-platform solution based on different "modules" (Core, Authenticator, Concealer and WhiteBox).

Strengths
  • Cross-platform (Android, iOS)
  • Strong Code and Flow obfuscation
  • Strong cryptographic key protection

Cautions
  • Price could be higher than expected

Company website: www.metaforic.com

WhiteCryption

This analysis pertains to whiteCryption's Cryptanium.
WhiteCryption provides code protection solutions since 2009, so they are relatively new on this market compared to Arxan or Metaforic. However they offer an innovative product that is designed to protect applications at all levels.

Strengths
  • Cross-platform (Android, iOS)
  • Strong Code and Flow Obfuscation
  • Strong anti-tampering protection
  • Anti-debug and anti-piracy features

Cautions
  • White-box cryptography techniques are still adopted very little

Company website: www.whitecryption.com

PreEmptive

This analysis pertains to DashO and .NET Obfuscator.
The first version of DashO was released in 1998 and .NET Obfuscator was initially released few years later. Therefore PreEmptive has a long experience in Code protection.


Strengths
  • Cross-platform (Android and Windows Phone)
  • Strong code and flow obfuscation
  • Watermarking
  • Tamper prevention and reaction

Cautions
  • No iOS support

Company website: www.preemptive.com

GuardSquare - Saikoa

This analysis pertains to DexGuard.
GuardSquare is very famous since they develop and support ProGuard, that is the successful open source obfuscator for the Java language. DexGuard is derived from it.
They have a great experience in Java and Android platform.

Strengths
  • Large adoption among our customers
  • Strong code optimization and obfuscation 
  • Anti-tamper detection

Cautions
  • Available only for Android

Company website: www.saikoa.com

Licel

This analysis pertains to Licel's DexProtector.
Licel is a new competitor in code protection. Its product, DexProtector, is designed for comprehensive protection of Android-applications against reverse engineering and tampering.

Strengths
  • Affordable for our clients
  • Strong code obfuscation
  • Anti-tamper detection

Cautions
  • Available only for Android

Company website: www.licelus.com

Bangcle - SecNeo

This analysis pertains to AppShield service. Bangcle provides a service that permits to developers to upload its APK on Bangcle's server and they provide fully automated App shield services. The whole process takes about one hour or less to complete.

Strengths
  • Very simple use
  • Anti-debug and Anti-tamper features
  • App Data Encryption

Cautions
  • Available only for Android

Company website: www.secneo.com

Smardec

This analysis pertains to Smardec's Allatori.
Smardec's main goal is to offer you high quality services and products at a reasonable price. Allatori first version was released in 2006 and it has reached these goals.

Strengths
  • Strong code and flow obfuscation
  • Watermarking
  • StackTrace restoring

Cautions
  • Available only for Android
  • Only code protection/obfuscation   

Company website: www.smardec.com

Zelix

This analysis pertains to Zelix KlassMaster.
Zelix has a long story and experience in code obfuscation. Since its release in 1997, the Zelix KlassMaster Java code obfuscator has been continually developed to keep it at the forefront of obfuscation technology.
This solution provides a Java code obfuscator but it does not implement other protections such as those against tampering tries.

Strengths
  • Strong code and flow obfuscation
  • Strong Call Hiding
  • Affordable for our clients

Cautions
  • Available only for Java (Android)
  • Only code protection/obfuscation

Company website: www.zelix.com

iMAS

This analysis pertains to iMAS.
This solution is free and open source, available on GitHub, and it provides modularity as the main feature. In particular the iMAS project is composed of many components that developers could include inside their project and every module provides a different feature. So it is up to the developers selecting the desired components and include them in the project.

Strengths
  • Free
  • Anti-tampering protections
  • Code encryption

Cautions
  • Available only for iOS
  • No after sale support

Company website: project-imas.github.io

Thursday, April 9, 2015

Beyond Superfish: a Journey on SSL MitM in the Wild

Recently Lenovo hit the news because they got caught installing adware on their laptops, namely Superfish, which, amongst other features, also perform SSL Mitm on the infected computer.

Unfortunately, Superfish is not the only one that has been caught nullifying end-to-end SSL encryption. Many other software and services are turning this "feature" into a nightmare: result is that nowadays SSL Man in the Middle is not an uncommon scenario at all.

But how widespread is it?
Thanks to Minded Security AMT Technology we are able to provide some insights since we monitor this kind of threat, being quite common to banking malware too: an example is Hesperbot that deploys an intercepting proxy on localhost to provide fake SSL certificates to its victims.

What we do is to analyse our client's users security stance to understand if they accept invalid certificates from external sources.

On any given day we can correlate unique users plagued by SSL MiTM to the presence of different adwares, not only SuperFish:

  • Superfish 8.36%
  • iMonomy: 5.35% 
  • JollyWallet: 4.01% 
  • FirstOffer: 2.00% 
  • DealPly: 0.33% 
  • InterYield: 0.32% 
  • jmp9: 0.30%

Those numbers are daily averages collected from a sample of two weeks traffic from over 1 year of logs. The following graph shows how a total of ~20% of Mitm'd users is correlated to an adware infection:



But there's more than just malwares when dealing with SSL interception. Many legitimate services underestimates this risk and accept it as a tradeoff for various gains.

That's the case of "cloud accelerated" browsers where users requests are cached on the cloud to provide a performance boost, like some versions of Opera Mini, Maxthon or Puffin that are not so uncommon and together are accounting for a 31.02% of total positive users we monitored.

On the Puffin Faqs we can read:
"All traffic from Puffin app to Puffin server are encrypted. It is safe to use public non-secure WiFi through Puffin, but not safe at all for most browsers."

Which highlights that the cloud server is used as a proxy, thus sending requests on behalf of the users.

It's not so clear instead for Maxthon. After the Superfish fiasco they published a note stating that even if yes, Maxthon users where positive to SSL MitM test, they were nonetheless secure:
"[...] Due to the way we handle javascript requests in our browser, Maxthon’s PC browser unintentionally triggers a false positive on the Superfish test. In most cases running the test on other browsers on your system will not. If you find yourself in a position where Maxthon is said to be insecure  and Chrome (on the same machine) is not, do not worry.  If you get positives from all browsers, you likely have Superfish.
To repeat: the way Maxthon browsers retrieve javascript can trigger a false positive during a Superfish detection test saying your system is at risk.  Even though our browsers remain as secure as the best in the industry, we recognize the severity of this bug and have elevated it to the top of the line – P1 importance."
According to our tests, Maxthon's Windows client application ignores SSL certificates on remote JavaScripts resources and AJAX requests. Fortunately, the annoying behaviour has been apparently fixed on v4.4.4.3000.

The idea to increase performance by caching or inspect the content of the data in transit is not used exclusively by cloud browsers.
In fact, we discovered some users using legitimate services like VPNs and triggering SSL Mitm alerts on our systems. For example HotSpot Shield (0.07%), SpotFlux VPN (0.02%), XO Cloud Services (0.51%), WebSense Cloud Security (0.03%) have an high correlation ratio.

From the SpotFlux website we read:
"Mobile data compression helps you save on bandwidth bills"
The following graph shows the percentage of services against the total of SSL Mitm'd users we monitored:



The classic SSL model is meant to protect  communications end-to-end,  but if user's connection is initiated or intercepted by the cloud service provider the purpose of this model falls short because the security of the SSL model depends on how the encryption keys are exchanged.



Lastly we observed a plethora of private networks like hotels, public hotspots, small companies that have an high correlation ratio but of which we couldn't identify a common cause other than a misconfiguration.

To sum it up SSL Mitm is a real common scenario with very different causes and broad consequences. We advise to be very wary of the software you are using on your devices since, as we've shown, even legitimate services and apps can pose a threat to your security profile.