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Mon, 22 Apr 2013

Google Docs XSS - no bounty today

A few days ago, during one of those nights with the baby crying at 2:00 am and the only thing you can do is to read emails, I realised that Gmail shows the content of compressed files when reading them in Google Docs. As often is the case at SensePost, the "think evil (tm)" came to me and I started to ponder the possibilities of injecting HTML inside the file listing. The idea is actually rather simple. Looking at the file format of a .zip file we see the following:



Every file in the compressed file must have two entries; ZipFileRecord and ZipDirEntry. Both of these entries contain the filename, but only the first one contains the length of filename (it must match the actual length). Our first test case is obvious; if we could modify this name once the file was compressed, would Google sanitise it? Thankfully, the answer is, yes! (go Google!)



As you can see, Google shows the file name inside the compressed file but the tag is displayed with HTML entities. If we then try to see the contents of the file, Google responds by telling us it's not possible to read the content of the file (it's empty) and shows you the file "without formatting" after a few seconds:



Finally, the filename is shown but not sanitised:



Why this is possible?


Remember that the zip format has the name of the compressed files twice. Google uses the first one (ZipFileRecord) for displaying the file names, but in the vulnerable page it uses the second one (ZipDirEntry).


Possible attack vectors


Going back to the 'thinking evil (tm)' mindset, it is now possible to leave a "comprehensive" name in the first entry and inject the malicious payload in the second one. When I first discovered the possibility of doing this, I contacted Google, however, the XSS is in the googleusercontent.com domain, which Google's security team described as a "sandbox" domain (i.e. we aren't injecting into the DOM of google.com) and therefore not worthy of a bounty. Which I accept, if I had to prove usefulness this could be used as part of a simple social engineering attack, for example:



Leading the victim to my phishing site:



Which then proceeds to steals their Google session, or allows the attacker to use BeEF:



Granted, there are simpler ways of achieving the same result. I just wanted to demonstrate how you can use file meta-information for such an attack.

Mon, 4 Mar 2013

Black Hat Europe - Bootcamp Training

Bootcamp
SensePost will be at Black Hat Europe 2013 to deliver the Bootcamp module of the Hacking by Numbers series. This method based introductory course emphasizes the structure, approach, and thought-processes involved in hacking (over tools and tricks). The course is popular with beginners, who gain their first view into the world of hacking, as well as experts, who appreciate the sound, structured approach.


A break down of what will be covered during this course:


  • Internet Reconnaissance

  • Internet Fingerprinting

  • Vulnerability Discovery

  • Exploiting Known Vulnerabilities

  • Finding and Exploiting Vulnerabilities in Web Applications

  • Attacking Content Management Systems

  • SQL Injection

  • Real-world exercises and capture-the-flags


To summarize:


What? SensePost Hacking by Numbers, Bootcamp edition
Where? Amsterdam, BlackHat EU
When? 12th & 13th March 2013
Level? Introductory


See the BlackHat course page for more information, or to book your seat.


We're looking forward to seeing you there!
Glenn & Sara

Vulnerability Management Analyst Position


Have a keen interest on scanning over 12000 IP's a week for vulnerabilities? Excited about the thought of assessing over 100 web applications for common vulnerabilities? If so, an exciting, as well as demanding, position has become available within the Managed Vulnerability Scanning (MVS) team at SensePost.


Job Title: Vulnerability Management Analyst


Salary Range: Industry standard, commensurate with experience


Location: Johannesburg/Pretoria, South Africa


We are looking for a talented person to join our MVS team to help manage the technology that makes up our Broadview suite and, more importantly, finding vulnerabilities, interpreting the results and manually verifying them. We are after talented people with a broad skill set to join our growing team of consultants. Our BroadView suite of products consists of our extensive vulnerability scanning engine, which looks at both the network-layer and the application layer, as well as our extensive DNS footprinting technologies.


The role of the Vulnerability Management Analyst will possess the following skills:


  • Be able to multitask and meet client deadlines. We want a person that thinks 'I can do that!'

  • Possess excellent written and oral communication skills. Being able to understand a vulnerability and explain it to business leaders is a must.

  • A working knowledge of enterprise vulnerability management products and remedial work flow

  • A broad knowledge of most common enterprise technologies and operating systems

  • A passion for security and technology


Some additional conditions:

  • A post graduate degree or infosec certification would be beneficial, however, showing us you have the passion and skills also helps

  • This job requires some after-hours and weekend commitments (we try to keep this to a minimum)

  • Bonus points for knowledge of sed, awk and python, ok even ruby.

  • PCI-QSA is desired but not required


Impress us with your skills by sending an email to jobs@sensepost.com and lets take it from there.


SensePost is an equal opportunity partner.

Sat, 2 Mar 2013

IT Network Packet Wrangler


As we grow and operate on a number of continents, so does our dependence on a rock-solid IT infrastructure. We are expanding our repertoire to include a greater collection of Linux/Open Source/Windows and OS X products. With this, we are on the look-out for a rock star to wrangle control of our internal networks, external cloud infrastructure and help us us utilise technology in a way to make us even better.


Job Title: IT Network Packet Wrangling Penguin Master


Salary Range: Industry standard, commensurate with experience


Location: Johannesburg/Pretoria, South Africa


Real Responsibilities:


  • Managing a growing internal network, both in ZA and UK and increased cloud-based infrastructure

  • Championing the adoption of new technologies, ways of working and being incredibly excited about security. Yes, we like that type of person who scoffs at the idea of using a plain-text protocol


As a system / network administrator your daily duties and responsibilities will include:

  • Providing day-to-day Desktop, Server and Network administration, including helping plakkers (the name we give to all who work at SensePost) with their devices

  • Be capable of using a variety of operating systems

  • Ensuring our disaster recovery plan is working as it should

  • Being the go to person to all those who require assistance with their IT

  • Maintaining and administer the telecommunications system

  • Administering the network to ensure that the systems in place run effectively and securely (we are, after all, a security company!)

  • A real passion for finding technology led solutions to problems.

  • Be excited about Unix firewalls, Cisco routers, wrangling network packets, VPN tunnelling and Wi-Fi

  • Able to hold a conversation and smile when mentioning SMTP/HTTP/IMAP/Python


Not essential, but bonus points for:

  • Actually getting a linux laptop to use an overhead projector, without resorting to swear words in Spanish and Afrikaans

  • Administering a Windows server without complaining, at all, not once, in fact, you actually kinda enjoy it.

  • Being really passionate about security and showing it doesn't have to get in the way of working productively.


If the above has got you thinking 'weird, it's like they are talking to me bru!' then we want to hear from you. Send us a carrier pigeon message or send us a mail