Windows OLE RCE Exploit MS14-060 (CVE-2014-4114) – Sandworm

Written on:October 22, 2014
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This recent exploit (dubbed “Sandworm”) took advantage of a vulnerability in which a specially crafted OLE object could allow remote code execution. In the case of the live sample exploit PPSX file I examined, it automatically downloaded the payload from a remote SMB share. I won’t rehash much of the details that others have covered but if you want to read more, here are some resources:

I downloaded a live exploit example from the following:

ms14_060_1

Again, others have explained how it works in detail, but I’ll cover it briefly here.

First, the PPSX file contains two binary OLE object binary files (oleObject1.bin and oleObject2.bin) that (thanks to the vulnerability) are able to define content to retrieve from a remote share.

ms14_060_2

Each is responsible for downloading one of the following two files:

  1. A malicious executable, posing as a GIF (slide1.gif).
  2. An INF file (slides.inf) that, when retrieved and executed, will rename the retrieved GIF to EXE.

The INF file would look something like this:

After examining the PPSX file, I generated a python script to re-create the exploit. The script creates the INF file along with a blank PPSX file, that when launched, will automatically call back to an SMB share hosted on a remote IP (as defined by the user) and retrieve the INF and GIF (EXE) files to trigger the exploit. It also provides the option to create a meterpreter reverse TCP executable to use as the payload (or you can use a payload of your choosing).

The created blank PPSX file can be modified to add content if you choose. The script utilizes python-pptx to create the blank PPTX file that it then modifies with the exploit and converts to a PPSX file. You can obtain python-pptx from here: http://python-pptx.readthedocs.org/en/latest/user/install.html#install. There is also a Metasploit Module, though I haven’t tried it yet.

Beyond the obvious patching, mitigating controls include host-based AV to detect both the crafted PPSX and the downloaded executable (as always, hit or miss), email AV (in the case of a phishing attempt via attachment), and network level protections (IPS and in this particular example, restricting outbound SMB traffic).

A short video and the POC code follow:

 

Drupal 7 SQL Injection (CVE-2014-3704)

Written on:October 17, 2014
Drupal 7 SQL Injection (CVE-2014-3704)

Introduction This vuln has been getting a lot of attention, and rightfully so. The good news is an update is available (and a supplemental patch has been released as well). The bad news is that it’s pre-auth SQLi. The basic problem is the way Drupal core 7.x versions prior to 7.32 construct a SQL query. Contrary to some claims, this is not a flaw in the use of prepared statements/parameterized queries, which…

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Written on:October 10, 2014
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Shellshock – Targeting Non-CGI PHP

Written on:September 30, 2014
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I’ve seen debates as to whether or not it’s possible to have an unpatched PHP server running in mod_php mode (i.e. not CGI) that is vulnerable to Shellshock. From my testing, the answer appears to be Yes…with some prerequisite conditions. First, the PHP application would have to be using Bash for its system commands — exec(), passthru(), system(), popen(), etc. This is pretty obvious since Shellshock is a Bash-specific vulnerability. Although PHP system command…

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Written on:September 28, 2014
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Introduction By now there are hundreds or even thousands of posts and articles about the Bash “Shellshock” vuln and more will be written tomorrow (and the next day …). With that in mind, this post will be fairly short and I won’t be rehashing what shellshock is or why it’s a problem. For that you can simply Google “shellshock” and you’ll find all you wanted to know and more. If you want…

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Written on:September 23, 2014
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Let me start this post by saying I’m a huge Google fan. I use multiple Android devices and like many others, I’ve become an avid user of services such as Gmail, Docs, Maps, Photos, and Youtube. I even find myself fondly reminiscing about discontinued services such as Reader. And, if you’re like me, Google search has become an instrumental tool in your professional endeavors. So please keep in mind, this post is…

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Written on:September 3, 2014
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Introduction In this seventh installment of the Windows Exploit Development Series, I’ll introduce Unicode Buffer Overflows. We’ll start with a brief introduction to Unicode (what it is and why/how it’s used in Windows) and then jump right in to some example exploits. If you plan on following along, I recommend you have the following: A Windows environment (XP or Win 7 — my demos will be on the latter) Metasploit, Alpha2 or…

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Written on:July 21, 2014
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Written on:May 6, 2014
dbir2014_44

Intro This year’s challenge was quite…well…challenging. Unfortunately Andrij, Will, and I were not able to repeat last year’s win and had to settle for second place. Frankly, at one point we weren’t sure we were going to finish at all, so we’ll take it! Read on to see our approach to finding the clues and solving the puzzle – and all of the frustrating missteps along the way. Day 0…

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Written on:April 20, 2014
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Introduction A recently published vulnerability prompted me to take another look at the wp_validate_auth_cookie WordPress function which is responsible for validating authenticated user requests and ultimately controls access to to your WordPress installation. This post is not about that specific vulnerability (more info here) but rather about how WordPress generates and validates authentication cookies to authorize user requests. If you’re a WordPress user, I encourage you to read on to see what stands between malicious actors and…

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