Vulnerabilities / Threats

12/6/2017
11:30 AM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

How the Major Intel ME Firmware Flaw Lets Attackers Get 'God Mode' on a Machine

Researchers at Black Hat Europe today revealed how a buffer overflow they discovered in the chip's firmware can be abused to take control of a machine - even when it's turned 'off.'

A recently discovered and now patched vulnerability in Intel microprocessors could be used by an attacker to burrow deep inside a machine and control processes and access data - even when a laptop, workstation, or server is powered down.

Researchers who discovered the flaw went public today at Black Hat Europe in London with details of their finding, a stack buffer overflow bug in the Intel Management Engine (ME) 11 system that's found in most Intel chips shipped since 2015. ME, which contains its own operating system, is a system efficiency feature that runs during startup and while the computer is on or asleep, and handles much of the communications between the processor and external devices.

An attacker would need physical, local access to a victim's machine to pull off the hack, which would give him or her so-called "god mode" control over the system, according to Positive Technologies security researchers Mark Ermolov and Maxim Goryachy, who found the flaw.

And although Intel issued a security advisory and update for the vulnerability on November 20, Ermolov and Goryachy argue that the fix doesn't prevent an attacker from using other vulnerabilities for the attack that Intel also patched in the recent ME update, including buffer overflows in the ME kernel (CVE-2017-5705), the Intel Server Platform Services Firmware kernel (CVE-2017-5706), and the Intel Trusted Execution Engine Firmware kernel (CVE-2017-5707).

All the attacker would have to do is convert the machine to a vulnerable version of ME and exploit one of the older vulns in it, they say. Those flaws "have been patched by Intel through its latest firmware release, but if an attacker has write access to the Management Engine region, they can downgrade to an older, vulnerable version of Management Engine and exploit a vulnerability that way," Goryachy told Dark Reading.

"Unfortunately, it's not possible to completely defend against this [buffer overflow] flaw" in the Intel ME, he says.

Intel OEMs can mitigate such attacks by turning off the manufacturer mode of the chip, he says. That way, they "make sure that a local vector attack … is not possible," notes Goryachy.

How the Attack Works

An attacker would need access to the "write" feature in ME, which is part of the SPI-flash chip that contains the firmware for ME and the BIOS, according to the researchers. He or she would then rewrite the flash and run a buffer overflow exploit, which would give him or her access to the ME.

"An attacker will have almost full control at the target machine, with access to memory, USB devices, and the network," Goryachy  says. "With this, an attacker could decrypt an encrypted hard disk of someone using Microsoft Bitlocker, or access content protected by DRM [Digital Rights Management], or intercept all activity on the PC, such as viewing what's on the screen, intercepting what's typed on the keyboard, and accessing data stored on disks."

It's up to Intel's OEMs to issue firmware updates, and Intel in its security advisory last month urged customers to check with their system OEMs for the updates. Enterprises also can use the open-source CHIPSEC utility to check for BIOS configuration errors, Goryachy says, and update to the latest version of the BIOS.

The Intel processors affected by the flaw are: 6th, 7th & 8th Generation Intel Core; Xeon E3-1200 v5 & v6 Product Family; Xeon Scalable Family; Xeon W Family; Atom C3000 Family; Apollo Lake Intel Atom E3900 series; Apollo Lake Intel Pentium; and CeleronG, N and J series.

This is the second major firmware vulnerability issue for Intel this year. In early May, the company disclosed a critical privilege-escalation bug in its Active Management Technology (AMT) firmware used in many Intel chips that affected AMT firmware versions dating back to 2010.

"Over the past 12 years, only two vulnerabilities allowing the execution of arbitrary code on Management Engine have been found," Goryachy says. "The AMT vulnerability only allows an attacker to bypass authentication. The vulnerability Positive Technologies discovered enables an attacker to insert invisible backdoors on a target machine."

Related Content:

Kelly Jackson Higgins is Executive Editor at DarkReading.com. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
It Takes an Average of 3 to 6 Months to Fill a Cybersecurity Job
Kelly Jackson Higgins, Executive Editor at Dark Reading,  3/12/2019
Box Mistakes Leave Enterprise Data Exposed
Dark Reading Staff 3/12/2019
How the Best DevSecOps Teams Make Risk Visible to Developers
Ericka Chickowski, Contributing Writer, Dark Reading,  3/12/2019
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win a Starbucks Card! Click Here
Latest Comment: LOL  Hope this one wins
Current Issue
5 Emerging Cyber Threats to Watch for in 2019
Online attackers are constantly developing new, innovative ways to break into the enterprise. This Dark Reading Tech Digest gives an in-depth look at five emerging attack trends and exploits your security team should look out for, along with helpful recommendations on how you can prevent your organization from falling victim.
Flash Poll
The State of Cyber Security Incident Response
The State of Cyber Security Incident Response
Organizations are responding to new threats with new processes for detecting and mitigating them. Here's a look at how the discipline of incident response is evolving.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2019-6149
PUBLISHED: 2019-03-18
An unquoted search path vulnerability was identified in Lenovo Dynamic Power Reduction Utility prior to version 2.2.2.0 that could allow a malicious user with local access to execute code with administrative privileges.
CVE-2018-15509
PUBLISHED: 2019-03-18
Five9 Agent Desktop Plus 10.0.70 has Incorrect Access Control (issue 2 of 2).
CVE-2018-20806
PUBLISHED: 2019-03-17
Phamm (aka PHP LDAP Virtual Hosting Manager) 0.6.8 allows XSS via the login page (the /public/main.php action parameter).
CVE-2019-5616
PUBLISHED: 2019-03-15
CircuitWerkes Sicon-8, a hardware device used for managing electrical devices, ships with a web-based front-end controller and implements an authentication mechanism in JavaScript that is run in the context of a user's web browser.
CVE-2018-17882
PUBLISHED: 2019-03-15
An Integer overflow vulnerability exists in the batchTransfer function of a smart contract implementation for CryptoBotsBattle (CBTB), an Ethereum token. This vulnerability could be used by an attacker to create an arbitrary amount of tokens for any user.