Thursday, December 17, 2015

(In)secure iOS Mobile Banking Apps – 2015 Edition

By Ariel Sanchez

Two years ago, I decided to conduct research in order to obtain a global view of the state of security of mobile banking apps from some important banks.
In this blog post, I will present my latest results to show how the security of the same mobile banking apps has evolved.


My research included 40 mobile banking apps with the following global distribution:

The metrics I used for this research are the same as before:
  • Limited to iOS platform
  • Black box approach
  • All tests were only performed on the app (client side); my research excluded any server-side testing
  • This research does not describe the vulnerabilities I found or how to exploit them in order to protect the owners of the apps and their customers
  • Some of the affected banks were contacted, and the vulnerabilities reported

Wednesday, December 9, 2015

Maritime Security: Hacking into a Voyage Data Recorder (VDR)

by Ruben Santamarta @reversemode

In 2014, IOActive disclosed a series of attacks that affect multiple SATCOM devices, some of which are commonly deployed on vessels. Although there is no doubt that maritime assets are valuable targets, we cannot limit the attack surface to those communication devices that vessels, or even large cruise ships, are usually equipped with. In response to this situation, IOActive provides services to evaluate the security posture of the systems and devices that make up the modern integrated bridges and engine rooms found on cargo vessels and cruise ships. [1]

There are multiple facilities, devices, and systems located on ports and vessels and in the maritime domain in general, which are crucial to maintaining safe and secure operations across multiple sectors and nations.

Port security refers to protecting all of these assets from acts of piracy, terrorism, and other unlawful activities, such as smuggling. Recent activity appears to demonstrate that cyberattacks against this sector may have been underestimated. As threats evolve, procedures and policies must improve to take these new attack scenarios into account. For example,

This blog post describes IOActive’s research related to one type of equipment usually present in vessels, Voyage Data Recorders (VDRs). In order to understand a little bit more about these devices, I’ll detail some of the internals and vulnerabilities found in one of these devices, the Furuno VR-3000.

Wednesday, November 25, 2015

Privilege Escalation Vulnerabilities Found in Lenovo System Update

By Sofiane Talmat @_Sud0

Lenovo released a new version of the Lenovo System Update advisory ( about two new privilege escalation vulnerabilities I had reported to Lenovo a couple of weeks ago (CVE-2015-8109, CVE-2015-8110). IOActive and Lenovo have issued advisories on these issues.

Before digging into the details, let’s go over a high-level overview of how the Lenovo System Update pops up the GUI application with Administrator privileges.

Thursday, November 19, 2015

Breaking into and Reverse Engineering iOS Photo Vaults

 By Michael Allen @_Dark_Knight_

Every so often we hear stories of people losing their mobile phones, often with sensitive photos on them. Additionally, people may lend their phones to friends only to have those friends start going through their photos. For whatever reason, a lot of people store risqué pictures on their devices. Why they feel the need to do that is left for another discussion. This behavior has fueled a desire to protect photos on mobile devices.

One popular option are photo vault applications. These applications claim to protect your photos, videos, etc. In general, they create albums within their application containers and limit access with a passcode, pattern, or, in the case of newer devices, TouchID.

I decided to take a look at some options for the iOS platform. I did a quick Google search for “best photo vaults iOS” and got the following results:

Figure 1: Search results for best iOS photo vaults

Friday, October 16, 2015

Five Reasons Why You Should Go To BruCON

By Alejandro Hernández (@nitr0usmx)

BruCON is one of the most important security conferences in Europe. Held each October, the ‘Bru’ in ‘BruCON’ refers to Brussels, the capital of Belgium, where it all started. Nowadays, it’s held in the beautiful city of Ghent, just 55 mins from its origin. I had the chance to attend this year, and here are the five things that make it a great conference, in my opinion.

You can check out BruCON’s promo video here:

1. The conference
Great talks presented by international speakers; from deeply technical talks, to threat intelligence and other high-level stuff. You might run into people and friends from Vegas or another security conference.

A circular and well illuminated stage. You better not be caught taking a nap, unless you want a picture of yourself sleeping on the Internet.

(Shyama Rose (@pencilsareneat) talking about BASE jumping and risk)

While paid trainings take place two or three days before the conference, free workshops are available to the public during the two-day conference.


(Beau Woods (@beauwoods) giving a cool workshop named:
«Escalating Privileges Through Better Communication»)

While at BruCON, I presented my research on security deficiencies in electroencephalography (EEG) technologies. EEG is a non-invasive method of recording electrical brain activity (synaptic activity between neurons) taken from the scalp. EEG has increasingly been adopted across different industries, and I showed how the technology is prone to common network and application attacks. I demonstrated brain signal sniffing and data tampering through man-in-the-middle attacks, as well as denial-of-service bugs in EEG servers. Client-side applications that analyze EEG data are also prone to application flaws, and I showed how trivial fuzzing can uncover many of them. You can find the related material here: slides, demos (videos), and my live talk (video).

2. The city
The medieval architecture in Ghent will enchant you. It’s a really cool city, everywhere you look. Full of restaurants, cafes, and of course, pubs. Students from all ages also make this city full of vibe. You can easily spend two more days and enjoy all Ghent has to offer.

All of this is just around the corner from the venue.



3. The b33r
I’m not a b33r connoisseur, but most of the beers I tasted while in Ghent were, according to my taste, really good. Belgium is catalogued as one of the best beer countries in the world, which speaks for itself. In a nice gesture by the conference organizers, speakers were given a single bottle of a hard-to-find beer, Westvleteren 12, which has been rated as “the best beer in the world.” I have no idea know how they got them, as the brewer does not produce large amounts of this beer and only sells it to a select few people.

Beer at the venue, beer between talks, and there was even a night where we mixed good beer with ice cream. It was interesting.


4. The venue
The conference is held in the heart of the city, near all the hotels, just two or three blocks from where you’re most likely to stay. The organizers thought out every single detail to help you arrive right on time at the venue.

The main hall is perfect for networking and serves b33r, coffee, and food all day, not only during specific hours.

A renowned hacker DJ is dropping some bass or a pianist girl (computer scientist who wrote code for Google) took turns to make those moments even better.

Wouldn’t be a good conference without a Wall of Sheep; it was RickRolled though ;D

(Picture taken by @sehnaoui)

The party venue, just three blocks from the stage, had a good hacker ambience and a good sound atmosphere created by two well-known DJs: @CountNinjula & @KeithMyers.

(Picture taken by @wimremes)

5. The old video game consoles
If you’re not interested in a talk, or simply bored, just head upstairs and travel back in time with a whole hall of old consoles. “Here comes a new challenger” are accepted…as long as there’s b33r or money involved.


Well, that’s it, another great security conference for you to consider in the future.

Finally, thanks to all this year’s organizers and volunteers. Perhaps you’ll join in next year ;-)

(Photo taken by @SenseiZeon)


Tuesday, September 22, 2015

Is Stegomalware in Google Play a Real Threat?

By Alfonso Muñoz @mindcrypt

For several decades, the science of steganography has been used to hide malicious code (useful in intrusions) or to create covert channels (useful in information leakage). Nowadays, steganography can be applied to almost any logical/physical medium (format files, images, audio, video, text, protocols, programming languages, file systems, BIOS, etc.). If the steganographic algorithms are well designed, the hidden information is really difficult to detect. Detecting hidden information, malicious or not, is so complex that the study of steganalytic algorithms (detection) has been growing. You can see the growth in scientific publications (source: Scholar Google) and research investment by governments or institutions.

In fact, since the attacks on September 11, 2001, there has been a lot of discussion on the possibility of terrorists using this technology. See:

In this post, I would like to illustrate steganography’s ability to hide data in Android applications. In this experiment, I focus on Android applications published in Google Play, leaving aside alternative markets with lower security measures, where it is easier to introduce malicious code.

Is it possible to hide information on Google Play or in the Android apps released in it?

The answer is easy: YES! Simple techniques have been documented, from hiding malware by renaming the file extension (Android / tr DroidCoupon.A - 2011, Android / tr SmsZombie.A - 2012, Android / tr Gamex.A - 2013) to more sophisticated procedures (AngeCryption - BlackHat Europe October2014).

Let me show some examples in more depth:

Google Play Web (

Google Play includes a webpage for each app with information such as a title, images, and a text description. Each piece of information could conceal data using steganography (linguistic steganography, image steganography, etc.). In fact, I am going to "work" with digital images and demonstrate how Google "works" when there is hidden information inside of files.

To do this, I will use two known steganographic techniques: adding information to the end of file (EOF) and hiding information in the least significant bit (LSB) of each pixel of the image.

          PNG Images

You can upload PNG images to that hide information using EOF or LSB techniques. Google does not remove this information.

For example, I created a sample app (automatically generated - and uploaded several images (which you can see on the web) with hidden messages. In one case, I used the OpenStego steganographic tool ( and in another, I added the information at the end of an image with a hex editor.

The results can be seen by performing the following steps (analyzing the current images "released" on the website):

Example 1: PNG with EOF

Step 2: Loot at the end of the file :)

Example 2: PNG with LSB

Step 2: Recover the hidden information using Openstego (key=alfonso)


       JPEG Images

If you try to upload a steganographic JPEG image (EOF or LSB) to Google Play, the hidden information will be removed. Google reprocesses the image before publishing it. This does not necessarily mean that it is not possible to hide information in this format. In fact, in social networks such as Facebook, we can "avoid" a similar problem with Secret Book or similar browser extensions. I'm working on it...

In summary, based on the previous proofs, I can say that Google Play allows information to be hidden in the images of each app. Is this useful? It could be used to exchange hidden information (covert channel using the Google Play). The main question is whether an attacker could use information masked for some evil purpose. Perhaps they could use images to encode executable code that "will exploit" when you are visiting the web (using for example polyglots + stego exploits) or another idea. Time will tell…

APK Steganography

Applications uploaded to Google Play are not modified by the market. That is, an attacker can use any of the existing resources in an APK to hide information, and Google does not remove that information. For example, machine code (DEX), PNG, JPEG, XML, and so on.

Could it be useful to hide information on those resources?

An attacker might want to conceal malicious code on these resources and hinder automatic detection (static and dynamic analysis) that focuses on the code (DEX). A simple example would be an application that hides a specific phone number in an image (APT?).

The app verifies the phone number, and after a few clicks in a specific screen on a mobile phone, checks if the number is equal to that stored in the picture. If the numbers match, you can start leaking information (depending on the permissions allowed in the application).

I want to demonstrate the potential of Android stegomalware with a PoC. Instead of developing it, I will analyze an active sample that has been on Google Play since June 9, 2014. This stegomalware was developed by researchers at Universidad Carlos III de Madrid, Spain ( This PoC hides a DEX file (executable code) in an image (resource) of the main app. When the app is running, and the user performs a series of actions, the image recovers the "new” DEX file. This code runs and connects to a URL with a payload (in this case harmless). The "bad" behavior of this application can only be detected if we analyze the resources of the app in detail or simulate the interaction the app used for triggering the connection to the URL.

Let me show how this app works (static manual analysis):

Step 1: Download the APK to our local store. This requires a tool, such as an APK downloader extension or a specific web as

Step 2. Unzip the APK (es.uc3m.cosec.likeimage.apk)

Step 3. Using the Stegdetect steganalytic tool ( we can detect hidden information in the image “likeimage.jpg”. The author used the F5 steganographic tool (

likeimage.jpg : f5(***)

Step 4. To analyze (reverse engineer) what the app is doing with this image, I use the dex2jar and jd tools.

Step 5. Analyzing the code, we can observe the key used to hide information in the image. We can recover the hidden content to a file (bicho.dex).
java -jar f5.jar x -p cosec -e bicho.dex likeimage.jpg

Step 6. Analyzing the new file (bicho.dex), we can observe the connection to for downloading a payload.

Step 7. Analyzing the code and payload, we can demonstrate that it is inoffensive.

The code that runs the payload:

Is Google detecting these “stegomalware”?

Well, I don't have the answer. Clearly, steganalysis science has its limitations, but there are other ways to monitor strange behaviors in each app. Does Google do it? It is difficult to know, especially if we focus on "mutant” applications. Mutant applications are applications whose behavior could easily change. Detection would require continuous monitoring by the market. For example, for a few months I have analyzed a special application, including its different versions and the modifications that have been published, to observe if Google does anything with it. I will show the details:

Step 1. The mutant app is “Holy Quran video and MP3” ( Currently at

Step 2.  Analyzing the current and previous version of this app, I discover connections to specific URLs (images files). Are these truly images? Not all.

Step 3. Two URLs that the app connects to are very interesting. In fact, they aren’t images but SQLite databases (with messages in Turkish). This is the trivial steganography technique of simply renaming the file extension. The author changed the content of these files:

Step 4. If we analyze these databases, it is possible to find curious messages. For example, recipes with drugs.

Is Google aware of the information exchanged using their applications? This example does not cease to be a mere curiosity, but such procedures might violate the policy of publication of certain applications on the market or more serious things.

Figure: Recipes inside the file io.png (SQLite database)

In summary, this small experiment shows that we can hide information on Google Play and Android apps in general. This feature can be used to conceal data or implement specific actions, malicious or not. Only the imagination of an attacker will determine how this feature will be used...

Disclaimer: part of this research is based on a previous research by the author at ElevenPaths,