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
White House Cybersecurity Strategy at a Crossroads
Kelly Jackson Higgins, Executive Editor at Dark Reading,  7/17/2018
The Fundamental Flaw in Security Awareness Programs
Ira Winkler, CISSP, President, Secure Mentem,  7/19/2018
Number of Retailers Impacted by Breaches Doubles
Ericka Chickowski, Contributing Writer, Dark Reading,  7/19/2018
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win a Starbucks Card! Click Here
Latest Comment: This comment is waiting for review by our moderators.
Current Issue
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2018-14512
PUBLISHED: 2018-07-23
An XSS vulnerability was discovered in WUZHI CMS 4.1.0. There is persistent XSS that allows remote attackers to inject arbitrary web script or HTML via the form[nickname] parameter to the index.php?m=core&f=set&v=sendmail URI. When the administrator accesses the "system settings - mail ...
CVE-2018-14513
PUBLISHED: 2018-07-23
An XSS vulnerability was discovered in WUZHI CMS 4.1.0. There is persistent XSS that allows remote attackers to inject arbitrary web script or HTML via the form[content] parameter to the index.php?m=feedback&f=index&v=contact URI.
CVE-2018-14514
PUBLISHED: 2018-07-23
An SSRF vulnerability was discovered in idreamsoft iCMS V7.0.9 that allows attackers to read sensitive files, access an intranet, or possibly have unspecified other impact.
CVE-2018-14515
PUBLISHED: 2018-07-23
A SQL injection was discovered in WUZHI CMS 4.1.0 that allows remote attackers to inject a malicious SQL statement via the index.php?m=promote&f=index&v=search keywords parameter.
CVE-2018-14517
PUBLISHED: 2018-07-23
SeaCMS 6.61 has two XSS issues in the admin_config.php file via certain form fields.