Updated:11:53 AM EDT Oct 14


this is ggmania.com subsite Hacker Finds Hidden \'God Mode\' on Old x86 CPUs - TechAmok

Hacker Finds Hidden 'God Mode' on Old x86 CPUs - [security]
11:42 AM EDT - Aug,12 2018 - post a comment

Some x86 CPUs have hidden backdoors that let you seize root by sending a command to an undocumented RISC core that manages the main CPU, security researcher Christopher Domas told the Black Hat conference here Thursday (Aug. 9). The command - ".byte 0x0f, 0x3f" in Linux - "isn't supposed to exist, doesn't have a name, and gives you root right away," Domas said, adding that he calls it "God Mode."

The backdoor completely breaks the protection-ring model of operating-system security, in which the OS kernel runs in ring 0, device drivers run in rings 1 and 2, and user applications and interfaces ("userland") run in ring 3, furthest from the kernel and with the least privileges. To put it simply, Domas' God Mode takes you from the outermost to the innermost ring in four bytes.

The good news is that, as far as Domas knows, this backdoor exists only on VIA C3 Nehemiah chips made in 2003 and used in embedded systems and thin clients. The bad news is that it's entirely possible that such hidden backdoors exist on many other chipsets.


Add your comment (free registrationrequired)

Short overview of recent news articles

Oct,14 2018 Facebook Wants to Put Video Cameras in Your Private Spaces
Oct,14 2018 Apple Plans to Give Away Original Content for Free to Device Owners
Oct,14 2018 Netflix cancels Marvel's Iron Fist
Oct,14 2018 Jonathan Trailer #1 (2018)
Oct,13 2018 Intel Core i9 9900K vs AMD Ryzen 7 2700X
Oct,12 2018 Samsung Says Foldable Phone to Act Like Tablet
Oct,12 2018 Facebook Says Hackers Accessed Users' Personal Data
Oct,12 2018 Maria Doroshina - Fit Russian Blonde Beauty
Oct,12 2018 2018 Most Popular Women Tennis Players
Oct,12 2018 AMD Radeon Adrenalin 18.10.1 Drivers
Oct,12 2018 NVIDIA GeForce 416.34 WHQL Game Ready Drivers
Oct,11 2018 Could You Answer Elon Musk's Tricky Interview Question?
Oct,11 2018 Samsung Galaxy A9 Adopts 4-Camera Configuration
Oct,11 2018 Fortnite for Android No Longer Requires An Invitation
Oct,11 2018 Samsung reported to be dropping 3.5mm jack with Galaxy S11 and Note
Oct,10 2018 Asus Confirms Plans to Sell ROG Phone In the US for $899
Oct,10 2018 Haunted - Official Trailer [HD] | Netflix
Oct,10 2018 Pet Sematary Trailer #1 (2019)
>> News Archive <<

TechAmok - Privacy Policy        loading time:0.01secs