...stuff I do and things I like...

Saturday, August 05 2017

RE-Canary: Detecting Reverse Engineering with Canary Tokens

This blog post is to provide some more details about my idea that was mentioned on Risky Business #463 by Haroon Meer.

What are Canary Tokens (from Thinkst).
    You'll be familiar with web bugs, the transparent images which track when someone opens an email. They work by embedding a unique URL in a page's image tag, and monitoring incoming GET requests.

    Imagine doing that, but for file reads, database queries, process executions, patterns in log files, Bitcoin transactions or even Linkedin Profile views. Canarytokens does all this and more, letting you implant traps in your production systems rather than setting up separate honeypots.
    ...
    Canary tokens are a free, quick, painless way to help defenders discover they've been breached (by having attackers announce themselves.)


The idea: Embed Canary Tokens into binaries (or application data) to help identify reverse engineering of your software.

Every reverse engineer looks for unique information (often just strings) in the target binary to help understand it. The strings are thrown into Google (or other search engines) with the hope to get additional information. The returned information can be extremely helpful to determine what the software is, what other code is linked in, what versions, etc. Everybody who reverse engineers stuff does this! I personally don't reverse engineer for a living so I asked around to confirm that professionals actually do this (I already knew the answer anyway!).

The plan:
  • Embed unique looking strings into the binary
  • Stand-up web page that contains the string, log access to that page (alert on access)
  • Make Google crawl that page (various tools for that)
  • Ship software

This is pretty straight forward, right? But do you care about somebody who just ran strings on your binary? Likely not! So what's next?

Many applications protect their code and other assets that come with it through different kinds of methods (called obfuscation techniques for this article - even not all of it will be actual obfuscation). The next step for the RE-canaries is to generate canaries and embed them into each obfuscation layer. If someone accesses a more obfuscated canary you know that a certain level of effort was put into reversing your app. This part is really where the creativity of the RE-canary deployment comes into play. This will be highly depended on the specific software, on the protection mechanisms used, the language and framework that app is written in and so on. Mobile apps (I'm a mobile app guy, yeah!) contain API endpoints and URLs and maybe some hardcoded credentials (tokens of course). The URLs have the advantage that you wouldn't need to put up a website. You just make them accessible and add logging and alerting.

The final part of this is automation. You want to automate canary creation and embedding into your built process, so that you can generate unique canaries with each built or major release or whatever fits your software.

In the end it will likely happen that advanced REs are going to use an anonymization service such as TOR when searching for strings or trying out URLs (specifically for URLs!). In this case at least you will know that someone is looking at your stuff and passed a certain skill/time/effort threshold, which I guess in most cases is enough information.

That's it! This idea was inspired heavily by Haroon Meer's Canarytokens a great free service that I use once in awhile!

Comments and feedback is welcome via the usual channels.

Thursday, July 13 2017

Mobile Security News Update July 2017

Conferences
    Black Hat USA Las Vegas, July 26-27. ALL YOUR SMS & CONTACTS BELONG TO ADUPS & OTHERS by Angelos Stavrou, Azzedine Benameur, Ryan Johnson. NEW ADVENTURES IN SPYING 3G AND 4G USERS: LOCATE, TRACK & MONITOR by Altaf Shaik, Andrew Martin, Jean-Pierre Seifert, Lucca Hirschi, Ravishankar Borgaonkar, Shinjo Park. SS7 ATTACKER HEAVEN TURNS INTO RIOT: HOW TO MAKE NATION-STATE AND INTELLIGENCE ATTACKERS' LIVES MUCH HARDER ON MOBILE NETWORKS by Martin Kacer, Philippe Langlois. FIGHTING TARGETED MALWARE IN THE MOBILE ECOSYSTEM by Andrew Blaich, Megan Ruthven. GHOST TELEPHONIST LINK HIJACK EXPLOITATIONS IN 4G LTE CS FALLBACK by Haoqi Shan, Jun Li, Lin Huang, Qing Yang, Yuwei Zheng. HONEY, I SHRUNK THE ATTACK SURFACE – ADVENTURES IN ANDROID SECURITY HARDENING by Nick Kralevich. DEFEATING SAMSUNG KNOX WITH ZERO PRIVILEGE by Di Shen. BLUE PILL FOR YOUR PHONE by Oleksandr Bazhaniuk, Yuriy Bulygin. CLOAK & DAGGER: FROM TWO PERMISSIONS TO COMPLETE CONTROL OF THE UI FEEDBACK LOOP by Chenxiong Qian, Simon Pak Ho Chung, Wenke Lee, Yanick Fratantonio.

    Defcon Las Vegas. Jailbreaking Apple Watch by Max Bazaliy. Inside the "Meet Desai" Attack: Defending Distributed Targets from Distributed Attacks by CINCVolFLT (Trey Forgety). macOS/iOS Kernel Debugging and Heap Feng Shui by Min(Spark) Zheng & Xiangyu Liu. Using GPS Spoofing to Control Time by David "Karit" Robinson. Phone System Testing and Other Fun Tricks by "Snide" Owen. Unboxing Android: Everything You Wanted To Know About Android Packers by Avi Bashan & Slava Makkaveev. Ghost in the Droid: Possessing Android Applications with ParaSpectre by chaosdata. Ghost Telephonist' Impersonates You Through LTE CSFB by Yuwei Zheng & Lin Huang. Bypassing Android Password Manager Apps Without Root by Stephan Huber & Siegfried Rasthofer. Man in the NFC by Haoqi Shan & Jian Yuan.

    USENIX Workshop on Offensive Technologies (WOOT) Vancouver Canada, 14-15 August. Shattered Trust: When Replacement Smartphone Components Attack by Omer Shwartz, Amir Cohen, Asaf Shabtai, and Yossi Oren. White-Stingray: Evaluating IMSI Catchers Detection Applications by Shinjo Park and Altaf Shaik, Ravishankar Borgaonkar, Andrew Marti, Jean-Pierre Seifert. fastboot oem vuln by Roee Hay.
Black Hat and Defcon have a really good number of mobile related talks this year.

It was a busy month and July will be even busier. I'll be at GSMA DSG, Black Hat and Defcon July and Usenix WOOT in mid August



Picture of month:


There is a lot happening in the Android boot loader world at the moment. I guess this is what happens when the devices get more and more locked down - people go after the root of trust.

Links:

Tuesday, June 06 2017

Mobile Security News Update June 2017

Conferences
    Black Hat USA July 26-27 Las Vegas. 'GHOST TELEPHONIST' LINK HIJACK EXPLOITATIONS IN 4G LTE CS FALLBACK by Haoqi Shan, Jun Li, Lin Huang, Qing Yang, Yuwei Zheng. ALL YOUR SMS & CONTACTS BELONG TO ADUPS & OTHERS by Angelos Stavrou, Azzedine Benameur, Ryan Johnson. BROADPWN: REMOTELY COMPROMISING ANDROID AND IOS VIA A BUG IN BROADCOM'S WI-FI CHIPSETS by Nitay Artenstein. CLOAK & DAGGER: FROM TWO PERMISSIONS TO COMPLETE CONTROL OF THE UI FEEDBACK LOOP by Chenxiong Qian, Simon Pak Ho Chung, Wenke Lee, Yanick Fratantonio. DEFEATING SAMSUNG KNOX WITH ZERO PRIVILEGE by Di Shen. FIGHTING TARGETED MALWARE IN THE MOBILE ECOSYSTEM by Andrew Blaich, Megan Ruthven. HONEY, I SHRUNK THE ATTACK SURFACE – ADVENTURES IN ANDROID SECURITY HARDENING by Nick Kralevich. NEW ADVENTURES IN SPYING 3G AND 4G USERS: LOCATE, TRACK & MONITOR by Altaf Shaik, Andrew Martin, Jean-Pierre Seifert, Lucca Hirschi, Ravishankar Borgaonkar, Shinjo Park. SONIC GUN TO SMART DEVICES: YOUR DEVICES LOSE CONTROL UNDER ULTRASOUND/SOUND by Aimin Pan, Bo Yang, Shangyuan LI, Wang Kang, Zhengbo Wang. SS7 ATTACKER HEAVEN TURNS INTO RIOT: HOW TO MAKE NATION-STATE AND INTELLIGENCE ATTACKERS' LIVES MUCH HARDER ON MOBILE NETWORKS by Martin Kacer, Philippe Langlois. THE FUTURE OF APPLEPWN - HOW TO SAVE YOUR MONEY by Timur Yunusov.

    (Black Hat has a very strong mobile security line up this year.)

    Defcon July 27-30 Las Vegas. Man in the NFC by Haoqi Shan & Jian Yuan. (speaker selection not final)

    MOSEC June, Shanghai added a bunch of talks (all mobile security related, obviously).

    Recon June 16-18 Montreal, Canada. FreeCalypso: a fully liberated GSM baseband by Mychaela Falconia. Hacking Cell Phone Embedded Systems by Keegan Ryan.
This took a long time again. It gets harder and harder do to this since this stuff is not directly what I do on a day to day basis currently.

The Qualcomm Mobile Security summit was excellent again! Fantastic talks and again I met a bunch of people I mostly knew from email and/or twitter or haven't seen in quite some time. This conference still is unparalleled!

I had a minute to play with the BlackBerry KeyOne and it feels like a super solid device. The screen is bigger then I thought it would be and this makes the device almost too big for my taste - but this is hard to say from playing with it for just a minute.

So iOS will finally support NDEF tags.
This talk is really interesting for anybody interested in mobile application security. This is not about mobile app reverse engineering but about app, backend, phone infrastructure interaction. Pictures of the month:





Links

Wednesday, May 10 2017

iOS WebView Dialer Fixed

In November 2016 I wrote a post about the iOS WebView Auto Dialer bug specifically in the iOS Twitter and the iOS LinkedIn apps. Last weekend I finally had the time to retest those apps to see if the bug was fixed. Retests in December and January showed the bug was still present (as far as I remember). Both apps are fixed now!

Playing around with this a bit more I discovered a new security warning on iOS. There now seems to be a detection for the case where a website automatically tries to open a TEL URL. The dialog doesn't always appear but when it does you first have to click allow before being presented with the actual Call/Cancel dialog. Neat!



The conclusion seems to be that the bug was fixed and that they added a new detection and warning dialog. Good!

Tuesday, April 25 2017

Mobile Security News Update April 2017

Conferences
    Black Hat USA July 22-27 Las Vegas. BROADPWN: REMOTELY COMPROMISING ANDROID AND IOS VIA A BUG IN BROADCOM'S WI-FI CHIPSETS by Nitay Artenstein. (Program not complete)

    SyScan360 May 30-31 Seattle. Exploit iOS 9.x Userland with LLDB JIT by Wei Wang. The wounded android WIFI driver New attack surface in cfg80211 by Hao Chen.

    MOSEC June, Shanghai. Revisiting the Kernel Security Enhancements in iOS 10 AND Pwning Apple Watch. (Program still not complete)


Recordings for the first OsmoCon are available here. OsmoCon is, of course, a conference about the OsmoCom projects!

Android O news: will prompt for pin/passcode before enabling developer options, further Android O changes device identifiers and how to access them.

If you are interested in mobile backing Trojans you should follow Lukas Stefanko:

Somebody released the source code of FlexiSpy (mobile phone spyware) to the public. The release notes are here: readme.txt. The download is here: FlexiSpyOmni.zip, collection of all data is here: Source code and binaries of FlexiSpy from the Flexidie dump and a writeup of the dump is here: FlexSpy Application Analysis. I bet we will see more details in the coming weeks!

Does Blackberry give out review samples for the KEYone? I would really like one and give it a try (would post full review here of course!).


All Nokia phones ever made.

Yo Ralf where the slides at?


Links

Tuesday, March 28 2017

Mobile Security News Update March 2017 part2

Conferences
    Qualcomm Mobile Security Summit 2017 San Diego, May. All talks are on mobile security - super strong lineup!

    AppSec EU May 11-12, Belfast. How to steal mobile wallet? - Mobile contactless payments apps attack and defense. Fixing Mobile AppSec: The OWASP Mobile Project.

    MOSEC June Shanghai. Pwning Apple Watch. (program not complete yet!)


OffensiveCon is a new security conference in Berlin Germany focused on Offense. No details yet but they chose the right location for sure.

For everybody who didn't make it to the Android Security Symposium, they recorded the talks and the videos are available: here.

Google published a blog post and a detailed report on Android Security in 2016. The report covers everything from patching and update stats to high impact vulnerabilities. People posted a lot of summaries but you should really read it yourself if you work with Android.

Google pulls March security update for Nexus 6, after it breaks SafetyNet and Android Pay. This was pretty interesting, not the fact that they broke SafetyNet but that they broke it for their own devices (Nexus). This happened to some really small manufacturer before and if you have an idea of how SN works on the backend - it is clear what happened.



Links

Tuesday, March 07 2017

Mobile Security News Update March 2017

Conferences
    Black Hat ASIA Singapore March 28-31. FRIED APPLES: JAILBREAK DIY by Alex Hude, Max Bazaliy, Vlad Putin. ANTI-PLUGIN: DON'T LET YOUR APP PLAY AS AN ANDROID PLUGIN by Cong Zheng, Tongbo Luo, Xin Ouyang, Zhi Xu. REMOTELY COMPROMISING IOS VIA WI-FI AND ESCAPING THE SANDBOX by Marco Grassi. 3G/4G INTRANET SCANNING AND ITS APPLICATION ON THE WORMHOLE VULNERABILITY by Guangdong Bai, Zhang Qing. MOBILE-TELEPHONY THREATS IN ASIA by Lion Gu, Marco Balduzzi, Payas Gupta. MASHABLE: MOBILE APPLICATIONS OF SECRET HANDSHAKES OVER BLUETOOTH LE by Yan Michalevsky.

    CanSecWest Vancouver Canada, March 15-17. Qidan He : Pwning Nexus of Every Pixel: Chain of Bugs demystified. Logic Bug Hunting in Chrome on Android by Georgi Hershey & Robert Miller.

    Zer0Con Seoul, Korea April 13-14. Ian Beer : Through the mach portal.

    OsmoCon (Osmocom Conference) 2017 is the first technical conference for Osmocom users, operators and developers! April 21, Berlin. All about Osmocom!

    HITB Amsterdam April 13-14. FEMTOCELL HACKING: FROM ZERO TO ZERO DAY by JeongHoon Shin. CAN'T TOUCH THIS: CLONING ANY ANDROID HCE CONTACTLESS CARD by Slawomir Jasek. EXTRACTING ALL YOUR SECRETS: VULNERABILITIES IN ANDROID PASSWORD MANAGERS by Stephan Huber, Steven Artz, Siegfried Rasthofer. HUNTING FOR VULNERABILITIES IN SIGNAL by Markus Vervier.

    Opcde Dubai, UAE April 26-27. Practical attacks against Digital Wallet by Loic Falletta.


I took a way too long break again. So many things happen in the world of mobile security every week. I really wish I had more time for this. I also have a bunch of small things I need to put on this blog but I think they are too specific for the news and will likely get their own posts.

Some news from MWC (I didn't attend):
    First the BlackBerry KEYone a new Android-based phone with a physical keyboard. Other then the BB Priv the KEYone's keyboard is fix and doesn't slide. Movable parts are really not a good idea, they break way too fast. In my opinion this device looks super solid and likely will be supported longer than the average flagship phone from other manufacturers (data on this would be awesome).

    Nokia released 3 new Android phones the 3 (MTK), 5 (QCOM) and 6 (QCOM). The phones seem to run Android N without any modifications or vendor crap. Very low price (230Euro for the 6). The bottom of their website specifically says: You get an experience that's focused and clutter-free, and we'll make sure you keep getting regular updates, so you'll always stay on top of features and security. that is what you should expect in 2017.


The Android Devices Security Patch Status page is an awesome resource to determine if a specific device from a specific vendor has been patched and when the patch was released. From the page: This list is Prepared to Serve as a Quick reference to identify which Device is being actively maintained by the Vendor.. This is super useful, thanks!







MOSEC mobile security conference in June in Shanghai. This seems to be the 3rd year of the conference. There is no schedule yet.

The story of the day Vault 7: CIA Hacking Tools Revealed. Vault 7: CIA Hacking Tools Revealed : iOS Exploit list. Yes, the CIA uses n-day exploits! The Android exploits.

They talk about Android, Defcon, and backdooring your repo? ;-)


Pic of the month:

Links