Last week, we decided to take a look onto the EMET library provided by Microsoft. This library is intended to introduce several security features to applications which are not explicitly compiled to use them.
It also adds an additional layer to protect against typical exploiting techniques by filtering library calls, preventing usage of dangerous functions/components and inserting mitigation technologies.
As EMET is already a target for many researchers, we currently only started to get an overview of it’s structure and how the different components are interacting with each other. Today we would like to share some of our results with you.
In a recent assessment, we had to evaluate how Microsoft’s System Management Server (SMS) certificate management solution (CMS) stores and handles certificates. This question came up because sensitive, encrypted user certificates were to be stored in the SMS CMS. Due to the sensitivity of the handled certificates, we assessed the protection capabilities of the certificate management solution against extraction attempts from a local attacker with administrative privileges.
Ever got a backdoor installed on your computer by your beloved mouse? Here’s the story of a poor mouse that got really, really sick.
Do you remember the times where people put Teensy-boards and USB hubs in their mouses? [Chris? ;)] Their aim was to attach an additional Human Interface Device (HID, like keyboards or mouses) with some payload in kind of e.g. keystrokes or mouse movements. Also, there are devices available like the USB Rubber Ducky in the housing of a USB thumb drive.
The principle is easy: The tools are using a programmable microcontroller with the capability to emulate USB HID. That’s it. Just program your board of choice with the payload fitting your needs and plug it in at the target computer. The latter will recognize it as a keyboard/mouse and the payload-keystrokes will be entered.
But why should external hardware be used? Many modern gaming peripherals provide functions to store macros on them, including enough onboard memory for little payloads.
While we were working on the layout of this years’ Troopers-Badge, I felt uncomfortable using my touchpad, so I switched over to a Logitech G-series gaming mouse. This one worked like a charm – many buttons and the feature to store personal profiles on the mouse itself, which is perfect when you work on more than one machine.
But wait – macros and profiles stored on the mouse? Recall the lines above concerning the HID story.
Could it be possible to store a macro big enough to drop a reverse shell on a Windows target?
Actually – it could.
It’s just as simple as using the Logitech Gaming Software’s Command Editor. Choose a button, put a macro on it, fit the timings and go!
The only thing you should consider, that you’re limited to about 100 keystrokes. If there should be something dropped on the target, like an executable or a script, you should think about using FTP or Powershell to download it externally, like I did here.
In this Proof of Concept the marco opens the Windows Command Line and downloads Netcat via Windows’ own ftp.exe from an external FTP server. Afterwards, it launches Netcat in background mode, while a Netcat listener already is waiting on the remote machine.
I think this kind of attack is dangerous due to its minimal effort and people trusting their mouses. Who would be afraid of a manipulated mouse, while being away for just 2 minutes to grab a cold Mate drink in the kitchen? The mouse’s software in this example offers the option to delay the keystrokes. Consider, the mouse acts like usual and after 30 or 60 seconds the bad magic happens, and it would take only a few seconds, so you might even miss the chance to see the windows popping up.
Usually I’m not the kind of guy who talks about such economic topics. Because I’m an engineer / security researcher who is exclusively concerned with understanding technical problems and if possible, solving them accordingly. My whole education is based on this and contains predominantly technical aspects of information security. This sometimes makes it difficult to understand what the market cares about (and why some products are being developed / exist on the market 😉 ). Nevertheless, a current engagement for one of our customers made me stumble upon such a product.
We were involved in a test where a security appliance (a black box 😉 ) played the core role. As you might know, the test procedure generally depends on the security question to be answered. In this case the question to be answered was, whether the black box provides the promised information security benefit. More specifically, we took a look at the environment / infrastructure, the protocols and the systems around it and checked if the black box does its magic. So the black box itself wasn’t in direct focus of the test. We were quite amazed about the blind trust the product received (but what else can one do, but trust the device they have already purchased ;-)? You can analyze it and that is what we did. Continue reading “How ‘security’ black boxes might corrupt your investment”
PowerView does not use the built in AD cmdlets to be independent from the Remote Server Administration Tools (RSAT)-AD PowerShell Module which is only compatible with PowerShell 3.0+ and by default only installed on servers that have Active Directory services roles. PowerView, however, is compatible with PowerShell 2.0 and has no outer dependencies. Furthermore, it does not require any installation process.
He is a security researcher in Google’s Project Zero. He has been involved with computer hardware and software security for over 10 years looking at a range of different platforms and applications. With a great interest in logical vulnerabilities he has numerous disclosures in a wide range of products from web browsers to virtual machine breakouts as well as being a Pwn2Own and Microsoft Mitigation Bypass bounty winner. He has spoken at a number of security conferences including Black Hat USA, CanSecWest, Bluehat, HITB, and Infiltrate. Continue reading “The Joy of Sandbox Mitigations”
In the last few years, attack techniques which fall in the categories of “Credential Theft” or “Credential Reuse” have grown into one of the biggest threats to Microsoft Windows environments. Microsoft has stated more than one time, that nearly almost all of their customers that run Active Directory have experienced “Pass-the-Hash” (PtH) attacks recently. Once an attacker gains an initial foothold on a single system in the environment it takes often less than 48 hours until the entire Active Directory infrastructure is compromised. To defend against this kind of attacks, a well-planned approach is required as part of a comprehensive security architecture and operations program. As breach has to be assumed, this includes a preventative mitigating control strategy, where technical and organizational controls are implemented, as well as preparations against insider attacks. This is mainly achieved by partitioning the credential flow in order to firstly limit their exposure and secondly limit their usefulness if an attacker was able to get them. Although we spoke last year at Troopers 15 about “How to Efficiently Protect Active Directory from Credential Theft & Large Scale Compromise”, we would like to summarize exemplary later in this post Active Directory pentest findings that we classified in four categories in order to better understand what goes typically wrong and thus has to be addressed. For a better understanding of the overall security goals, we classified the findings as to belonging as a security best practice violation of the following categories: Continue reading “TROOPERS16 Training Teaser: Dos and Don’ts of Secure Active Directory Administration”
In this blogpost we will briefly explain a well known Syscall hooking technique (a more detailed explanation can be gathered from e.g. http://resources.infosecinstitute.com/hooking-system-service-dispatch-table-ssdt/) used by multiple malware samples (like the laqma trojan) and right after discuss how some memory analysis tools have trouble in the analysis and/or reporting of these. Continue reading “Investigating Memory Analysis Tools – SSDT Hooking via Pointer Replacement”
This year’s Black Hat US saw a number of quite interesting talks in the context of Windows or Active Directory Security. For those of you too lazy to search for themselves 😉 and for our own Windows/AD Sec team (who couldn’t send anyone to Vegas due to heavy project load) I’ve compiled a little list of those.