"ENE Technology Inc" - vulnerable drivers global provider

Intro

Pic 1. Official logo.

ENE Technology Inc is a Taiwan based company founded in 1998. According to their website hxxp://www.ene.com.tw/index-en.php and Bloomberg summary:

ENE Technology Inc. develops, manufactures, and markets IC (integrated circuit) products. The Company's products include application-specific integrated circuits (ASICs), controller ICs for power switches, and notebook keyboards. 

However most of you will probably know them by piece of software - a ridiculously bugged driver bundle that ships with multiple software products of variety of hardware vendors, including but not limited to MicroStar, MicSys, ASUS, ASRock and some others. It is written by a very interesting developer(s) and I believe it is the same for all multiple variants of this driver bundle. The figure(s) behind this driver is awesome as I encounter their "creativity" multiple times and each time they manage to surprise me in a way when you expect that it can't be worse. 

Lets say what will happen when you hire someone with mediocre C-language understanding, who discovered official documentation just in 2020 but has a great google search skills? Nothing really bad, most of AV companies are full of such people (its a joke), but at least they have someone who can control them. ENE Technology Inc software products that will be discussed next is an example of what happens when no one control such people and their "creativity".

It's all about I/O

 

When it comes to hardware vendors giveio type drivers in 90% it is all based on three main sources:

• Windows DDK samples that are dated back to Windows NT 3.51 (hello Unwinder);
• WinRing0 open sourced library by hiyohiyo (CrystalMark author);
• WinIO open sourced library by Yariv Kaplan (from internals.com).
  

Just a coupe of bugs inside these sources:

1. No requestor access rights check - all driver devices are created with default security descriptor meaning everyone have read/write access to them;
2. No input parameters checking or they are insufficient/incorrect - easy way to crash your system from any user;
3. Unrestricted functionality - you can read/write anywhere, any ports, MSR's.
   

Currently hardware vendors are mostly blatantly copy-paste from these sources with minimal changes, if any. Sometimes their drivers contain functionality their products does not need at all. 

Reasons why this is a bad approach:

• All of the above were created without any kind of security in mind. It was forgivable to old DDK samples but totally inappropriate for everything else. So this code is failure by design and created with Windows XP in mind;
• Original codebase contain obvious programming mistakes - HW vendors mostly don't care and rarely fix anything.
  

It is a common trend for almost EVERY gaming hw vendors available today.

Pic 2. Choose your exploits provider.

When it comes to ENE Tech Inc drivers they are based on WinIO of 3.0 version. My first encounter was ASUS GLCKIo2 driver. 

Pic 3. ASUS locked GLCKIo2 driver.

 

It was all about same copy-pasta, but with ridiculous addition. This driver was "locked" for non trusted application access. This mean you have to "register" yourself as a good caller before doing any other job with this driver. This is fascinating - author more worried about who will be using his driver more than quality of driver code he copy-pasted. The "unlocking" process of GLCKIo2 driver was the following:

1. In client application - call GetCurrentProcessId(), modify result with SWAP_UINT32 macro;
2. Copy result to local 16 bytes length buffer;
3. Encrypt this buffer with AES ECB, using TinyAES open source code, as key they used slightly modified values found in Google search (😎);
4. Call driver with special IOCTL passing encrypted buffer as input parameter;
5. Driver processes this IOCTL, decrypts buffer (same TinyAES) and extracts PID to remember it in internal list of "trusted" applications;
6. When other IOCTL called - driver checks if this call is from process with ID in trusted list - if so call allowed, otherwise access denied error will be returned to caller. 

It is merely a joke than anything else. Full unlocking -> https://gist.githubusercontent.com/hfiref0x/3d46c012eb6cffcba34f0006d38e5165/raw/b2792823f85bdd4d5a91a8c802d6f57320ad2cc1/GLCKIo2.c

Next I found ENE.sys driver signed with "Ptolemy Tech Co" certificate. It was based on WinIO but missing all these locking features. Curiously enough it contain the following pdb string: d:\winglckio_20180320\amd64\EneIo.pdb

Pic 4. ENE lock free variant.

 

It is hard to tell which one was the first, but ASUS lock feature may have explanation. Well, ASUS drivers were loved target for CVE scalpers - easy to get and sort of "addition" to infosec portfolio. If you google for GLCKIo driver you will find a lot of CVE noise around it, for example https://seclists.org/fulldisclosure/2018/Dec/34. With initial discovery in the end of 2017. So we can assume that this GLCKIo2 is a sort of response.This could explain caller registration introduction and code base switch. As "fix" it is pathetic and fixes nothing. This is not an ASUS only fault - all the above mentioned companies does the same. In general they give zero fuck about security of their customers, especially MSI.

Looking for more ASUS bugged drivers (there are LOT of them) I found an interesting coupe next. AsIO.sys (device name Asusgio) and AsIO2.sys (device name Asusgio2). First driver is an old standard copy-paste which has CVE noise assigned, second one is from our beloved ENE Tech Inc coders.

Pic 5. AsIO2 from our friend.

 

Specific code similarities found inside both drivers led to idea that they are both created by same author/team. It is slightly modified WinIO codebase (no bugs fixed, instead added more chaos) with another "driver lock", implemented in unusual way. The unlocking is only allowed from process that has specific PE resource inside named "ASUSCERT". That is how it generated:

1.  Query current timestamp with GetSystemTimePreciseAsFileTime;
2.  Convert it to seconds since 1970;
   
3.  Copy value to 16 bytes length buffer and encrypt it using AES ECB (TinyAES again);
4. AES key again found in Google search and slightly modified;
5. Move result encrypted buffer to PE resources as "ASUSCERT" (without quotes).

When caller does request to the driver (any IRP_MJ_*) driver will query full image path of the caller, read file into buffer and parse for PE timestamp and RCDATA resource named ASUSCERT, decrypt it and extract timestamp. Next AsIO2 will check if the difference between PE timestamp and decrypred timestamp < 7200 (2 hours). If it is - then caller will be allowed to use driver. Thus to be able use this driver you just need a properly generated resource.

 

This obviously can't be threatened as security fix. 

Pic 6. Very secure, very fixed AsIO2.sys

 

Using same pattern I found several other drivers. For example driver called EneTechIo.sys (E:\GitSourceCode\Ene\SmbusSDK\driver_src\EneIo\x64\Release\EneIo.pdb)

Pic 7. EneTechIo driver from TOUGHRAM software bundle.

 

WinIO based, locked driver as usual. However they again changed unlocking algorithm. Instead of using PE resource they now passing encrypted buffer directly in each driver call as part of input data structure. Every payload driver function now checks if the call time within a small time window (few seconds). Unlocking it looks like this:

 

Worth to mention some debug version of Ene driver. It is lock free, has multiple DbgPrint's and contain the following pdb string (d:\winglckio_20180320\amd64\EneIo.pdb).
 

As of recent EneTechIo driver from fresh up-to-date of this post MSI Dragon Center bloatware (E:\GitSourceCode\IoAccess\SmbusSDK\driver_src\EneIo\x64\Release\EneIo.pdb).

Pic 8. EneTechIo from MSI Dragon Center (May 2020)

Key changes:

1. TinyAES is no longer used, they switched to CNG (maybe also found it while doing usual Google searches for copy-pasta ready code);
2. MSR related code removed;
3. Introduced new requestor whitelisting check.

Driver setups image load notify callback (PsSetLoadImageNotifyRoutine) and looks for event when SB_SMBUS_SDK.dll is loaded. Note that name of dll is case sensitive. This dll is an API layer for interacting with EneTech driver. If filename contains SB_SMBUS_SDK.dll then driver will register process by it ID extracted from notify callback. No further checks implemented, so basically you can create dumb empty dll with SB_SMBUS_SDK.dll name, load it in your process and this driver will register you as trusted caller. Everything else will be the same as AES encoding mode is same and their implementations of course has no differences.

Code to unlock -> https://gist.githubusercontent.com/hfiref0x/bff37d328cb16d3df92f8743b4b054ca/raw/595531f209771943cecce799afd954029ba02b80/enetech_new.c

ENE Tech Inc authors doing everything possible (for them) to complicate their driver usage by third-party actors. Instead of fixing generic WinIO "bugs and features" they constantly (and with no success) reinventing the wheel.

P.S. Very company, very ENE Technology Inc.

When I found their website in Feb 2020 I was very surprised by it English section, because it was all full of 3rd party web injected links.

Pic 9. Ene website.

 

Hashes:

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61a1bdddd3c512e681818debb5bee94db701768fc25e674fcad46592a3259bd0

06bda5a1594f7121acd2efe38ccb617fbc078bb9a70b665a5f5efd70e3013f50

9fc29480407e5179aa8ea41682409b4ea33f1a42026277613d6484e5419de374

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Unwinding RTCore

This is a response to recent Unwinder claims and behavior related to vulnerabilities found in his RTCore32/64 driver which is a part of MSI Afterburner. I almost forgot about him and his software but recently this guy reminded himself again.

RTCore overview
RTCore is a name of kernel mode driver used by MSI Afterburner software (https://www.msi.com/page/afterburner), quote "The world’s most recognized and widely used graphics card overclocking utility which gives you full control of your graphics cards". There are exist two variants of the RTCore driver, built from the same source - RTCore64.sys and RTCore32.sys, each for respective platform. This driver provides access to the physical memory, CPU MSR's, I/O ports read/write. Applications interact with driver via API layer implemented in RTCore.dll which is also a part of MSI Afterburner installation. Basically it is a simple "giveio" type helper driver.

This driver is a subject of legacy code, derived in mostly unmodified state likely from time when Windows XP (or even Windows 2k) was all new and shiny. That mean it doesn't care about security. Latest available RTCore drivers is able to run on most recent Windows 10 where enforced security was enabled. Historically RTCore is a part of RivaTuner code. In a short, RTCore is a wormhole.

Security issues of RTCore known for a long period of time, got various CVE id's and even caused author - Alexey Nicolaychuk aka Unwinder to publicly bitch about yet another publication (https://github.com/Barakat/CVE-2019-16098). TL;DR according to Alexey, no one notified him before publication, so it wasn't a "responsible disclosure". 

Is that true? Of course not, he was aware of this RTCore "feature" at least from 2016, see next.

It is worth to mention that I was using RivaTuner back to the 1999 and early 200x on Riva TNT2 next GeForce 2 MX400 and GeForce 3 Ti200 and this utility was indeed very helpful at that time. Than I got enough money to buy better hardware and RivaTuner moved to the Recycle Bin.

Response to CVE-2019-16098
No doubt his code and everything based on it is still very useful for a lot of people. However Alexey attitude to security of his products can only be described as "weird". This can be described by idiom "You can't teach an old dog new tricks".

Pic 1. Unwinder response to CVE-2019-16098.

Alexey probably unaware that this kind of bugs (vulnerabilities in third party drivers and especially in various utilities from hardware vendors) are common for years, and under "years" I mean YEARS (e.g. CVE-2008-5725). We still here and no apocalypse happened. He was so upset that he decided to write to the author of the exploit both on the github and on Twitter some mocking messages. Have no idea, probably if there was Facebook somewhere he would post here too, or already did? Well, what can I say, are you in need of some medicine, Alexey? This attitude is a common for some ex-USSR people who believe that sun is spinning around them and everybody owes something to them.

The Jar of Worms*
*(c) Unwinder, 2019
To understand what does this mean lets take as example UnknownCheats forum (UC) - probably the leading platform for game cheats developers available today. By it impact to the game cheats it probably can be compared to the wasm.ru impact on sophisticated malware development. Here, just by using forum search, you can find a multiple vulnerable drivers (even packs of them) with some already used in game cheats to bypass anticheat software. They use this for years and most of information freely available for both cheat/anticheat developers and very well indexed by search engines. Github is full of projects (of various quality) from UC members involving usage of these vulnerable drivers - these projects are provided as-is to everyone on various programming languages. While being written by mostly kids of school or college age 

Pic 2. Typical UC thread content
(https://www.unknowncheats.me/forum/2111513-post8.html).

they are usable as all you need from this is a concept.

Why there is no multiple use in malware area and where is the "jar of worms" located? So far this jar of worms exist only as Unwinder wet fantasy. If Alexey was not an amateur in the area where he is trying to picture himself as an expert (or if we go down to the Unwinder comments level - wannabeexpert) -  he would know about modern Windows security boundaries and thing called practicability. Difference between intentional and unintentional/forced usage. In cheats area - game hack users are actively involved in bypassing security mechanisms because they want to play with cheats and they ultimately looking for a way to do that. In malware - users are victims and while they can be social-engineered to bypass basic Windows security mechanisms in favour of malware needs, malware still will have to deal with Windows security. That moves practical usage of this drivers to the very specific APT area. 

RTCore problem
After dealing with "jar of worms" (yeah I like that) we suddenly discovering that RTCore author seems absolutely do not understand the "core" problem of his RTCore. Here is it, Alexey, specially for you - who are ignoring OS security model for decades, I'm showing you exact problem of your wormhole by design software.

Pic 3. RTCore DriverEntry.

Quote from MSDN

IoCreateDevice can only be used to create an unnamed device object, or a named device object for which a security descriptor is set by an INF file. Otherwise, drivers must use IoCreateDeviceSecure to create named device objects.


What happens here. When MSI Afterburner loads RTCore32/64 driver, it device object will be created with a default security descriptor. Which means literally any logged user on this machine can access this driver through it device with read/write permissions.

Pic 4. RTCore64 device security permissions.

RTCore gives you ability to read/write to the MSR's, I/O ports and memory. The first use of this RTCore "design" demonstrated by CVE-2019-16098 - elevation of privilege via typical EPROCESS structure modification. Another one (since this driver has ability to read/write arbitrary kernel memory) is driver mapping - something similar to TDL/Stryker/CapCom and multiple other mappers based on vulnerable third-party drivers. Since there is also feature to read and write to MSR's and ports - this makes RTCore awesome for exploiting.

Normally if your driver is something more complex than kernel mode "hello world" and has data read/write to user mode it must contain security checks. For example you can limit access to your driver using IoCreateDeviceSecure or/and check security context in your IOCTL handler, requester privileges etc - there are many ways to do that in the *right way*. If you for some reason cannot use shiny new APIs (for example, you are supporting Windows 2k 👻) you still can secure driver device using Rtl SD/Ace/Dacl documented APIs and ZwSetSecurityObject. It is not a problem.

The lack of security checking is a very common problem for software supposed to work with hardware. Few examples: system utilities (CVE-2017-15303), overclocking and other software from GPU/hardware vendors (CVE-2018-18536, CVE-2019-8372), hardware monitoring utilities (CVE-2018-8060, CVE-2018-8061), bios flashers (CVE-2019-5688) etc. A lot of them. Practically ALL drivers of that kind that I was investigating were vulnerable or based on vulnerable code. 

Pic 5. Choose your exploits provider.

If you need an example, here is it https://github.com/QCute/WinRing0/blob/master/dll/sys/OpenLibSys.c. This is open-source OpenLibSys driver from hiyohiyo who are now supposedly author of CrystalMark. The following driver named WinRing0 and used in multiple products up to date in mostly unmodified state (as WinRing0.sys, WinRing0x64.sys, could be different names). It lacks any security checks and just a wormhole driver by design. Its irony, but it has been reported as CVE-2017-14311 exploit for Netdecision 5.8.2 software few years ago. This driver is still used in various products in unmodified state. Here is a simple example how any unprivileged user can read/write to physical memory with help of that driver shipped together with EVGA Precision X OC v6.2.7. Probably this can be improved to local privileges elevation exploit similar to  CVE-2019-8372.

There is a nice collection of this kind of drivers with brief descriptions made by Eclypsium, https://github.com/eclypsium/Screwed-Drivers/blob/master/DRIVERS.md Please note that some vendors already provided new versions with improved security (for example Intel) and this list is incomplete, also you still can find exact old vulnerable drivers and use them.

If you look on "giveio" drivers from various vendors you will notice - they all almost the same, they only differ little in some implementation details and internal structures used to communicate with user mode. And they all of course signed 😊


RTCore wormhole*
*(c) hfiref0x, 2020
CVE-2019-16098 was targeting exact MSI Afterburner version - 4.6.2.15658, it is Afterburner 4.6.2 Beta 2. However given exploit will work with older versions of MSI Afterburner as they include same driver. In the next Afterburner version Unwinder proposed a fix for this CVE, you can find a little about it in the changelog (https://www.guru3d.com/files-details/msi-afterburner-beta-download.html) 

"Updated IO driver provides more secure MMIO and MSR access interface". 

More precisely it means that memory mapping IOCTLs now work only for hardware IO reserved address ranges. And he banned arbitrary MSR read/write, setting up restrictions on their IOCTLs. Driver also got EV certificate. This interesting though this exact "fixed" RTCore present only since MSI Afterburner 4.6.2 Beta 3, while it is pretty much similar to fixes announced by Unwider three years ago in comments to the rewolf post - MSI ntiolib.sys/winio.sys local privilege escalation. 

Pic 6. RTCore fix, announced in September 2016.

Even if this is, judging from Unwinder comment, partial fix - it is notable this updated RTCore component wasn't distributed with MSI Afterburner, until Barakat published his proof-of-concept and got CVE. How much other software with bundled RivaTuner code still not updated their RTCore related code base (even if these components may have different names)? Speaking about ethics, which is mentioned by Unwinder in above response to CVE-2019-16098, how does that correlates with it too? You have extremely vulnerable driver which code base used by different products, you have produced some "security related" changes, and for three years didn't even updated your own MSI Afterburner. Just because no one gives a single fuck until you got upset with publicly available CVE forcing you to jump to the twitter/issues shitpostings. This is hilarious, Unwinder. 

Okay, additions he made makes sense and question is only why there weren't here from the beginning. But seriously, is that the only problem this guy found? 😊 While Unwinder really likes to go on demagogy discussions about Windows security model, he still doesn't know how to use wdmsec.lib, maybe because MSI Afterbutner RTCore driver got compiled in something like Visual Studio 2005/2008 with DDK likely from Windows XP/Vista. No joke, just look at this driver structure. As you understand we still can use this driver for a range of bad things. For example for Denial of Service attack.

This is simple proof-of-concept code for "fixed" RTCore from MSI Afterburner 4.6.2.15745 release, it will write specific data to the I/O port to initiate immediate system reboot which can lead to data loss and/or potential hardware damage. From unprivileged, guest, whatever account. This of course will also work for previous variants of RTCore if they support required IOCTLs. That is not all - this driver still has a lot of potential, because there are multiple other IOCTLs.

The simple solution to that wormhole named RTCore is to move it into OS security boundary and stop bitching about self-made problems as Unwinder still does. Or do as I did many years ago - throw all these CD/DVDs supplied by GPU vendors with their crapware to the trashcan along with their authors as an ultimate solution to the security of this vector.