Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Endpoint

1/26/2010
01:51 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

New Attack Uses Internet Explorer's Own Features Against It

Microsoft investigating threat, considering patch, or offering guidance for protection

A researcher at Black Hat DC next week will demonstrate how an attacker can steal files from a victim's machine by abusing a combination of actual features in Internet Explorer.

Jorge Luis Alvarez Medina, a security consultant with Core Security Technologies, says popular features in IE, such as URL Security Zones and the browser's file-sharing protocol, can together be abused to execute an attack that results in the attacker being able to read all files on the victim's machine. Medina plans to release proof-of-concept code for the attack next month after Black Hat DC, and after Microsoft issues a security update for the attack, which affects IE versions 6 and above, he says.

"These vulnerabilities are just features ... the implementation of the features allow you to obtain certain information, which by itself is harmless. But when combined together with other features, it renders an attack vector," Medina says. The attack requires the user to click on a malicious link.

Microsoft had previously patched two vulnerabilities in URL Security Zones -- initially discovered by Core -- that allow an attacker to cheat the Security Zones feature. But the patches don't prevent this new attack, Medina says.

"In its hot fixes, Microsoft is just slightly modifying some of the features so they cannot be strung, but as their base design is insecure, most of them are still there," he says.

Dave Forstrom, group manager of Microsoft's Trustworthy Computing, says Microsoft is investigating the vulnerability and hasn't yet seen any attacks in the wild. "Once we're done investigating, we will take appropriate action to help protect customers. This may include providing a security update through the monthly release process, an out-of-cycle update or additional guidance to help customers protect themselves," Forstrom said in a statement. He says users in the meantime should upgrade to IE 8 and enable Microsoft's automatic update feature.

The attack basically abuses the way features in IE are designed, Medina says, and it only works when a combination of features are abused in the attacks. A single feature can't be abused to wage the attack, he says. It does not, however, allow the attacker to execute code remotely or to control the victim's machine.

With IE's Security Zones, an Internet zone would not be allowed to read files from a local machine, for instance, Medina says. But if a local machine is considered part of the Internet zone, its files could be accessed by an attacker, he says.

"There are certain conditions when dealing with local equipment where it doesn't behave as expected," he says. "If it refers to a local machine by its local machine name, the computer will be treated as if it belongs to the local intranet zone. But if it's referred to by its IP address, it will be treated as part of the Internet zone, which brings complications" and opens up the possibility of this attack, he says.

Another step in the attack would trigger an SMB connection between the victim's browser and the attacker's server, which forces a handshake between the two that exposes the victim's Windows user name and other identifying information.

"The attack is not that complicated," Medina says. "And the attacker can get any kind of files -- text or binary."

The attack doesn't apply to other browsers, even though many of them use the same features that IE does, Medina says. "The problem is not just in the feature itself, but in the way it's implemented," he says. And some of that has to do with IE's relationship with Windows Explorer in the operating system, he says.

There are a few ways to mitigate these attacks, Medina says, including deploying IE's Protocol Lockdown feature to restrict the file protocol; setting the security level to "High"; disabling active scripting in the Intranet and Internet Zones; running IE in Protected Mode if available in the OS; using a different Web browser when visiting untrusted sites; and locking down and disabling the MHTML protocol handler.

Have a comment on this story? Please click "Discuss" below. If you'd like to contact Dark Reading's editors directly, send us a message. Kelly Jackson Higgins is the Executive Editor of Dark Reading. 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
Zero-Factor Authentication: Owning Our Data
Nick Selby, Chief Security Officer at Paxos Trust Company,  2/19/2020
44% of Security Threats Start in the Cloud
Kelly Sheridan, Staff Editor, Dark Reading,  2/19/2020
Firms Improve Threat Detection but Face Increasingly Disruptive Attacks
Robert Lemos, Contributing Writer,  2/20/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
6 Emerging Cyber Threats That Enterprises Face in 2020
This Tech Digest gives an in-depth look at six emerging cyber threats that enterprises could face in 2020. Download your copy today!
Flash Poll
How Enterprises Are Developing and Maintaining Secure Applications
How Enterprises Are Developing and Maintaining Secure Applications
The concept of application security is well known, but application security testing and remediation processes remain unbalanced. Most organizations are confident in their approach to AppSec, although others seem to have no approach at all. Read this report to find out more.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-8813
PUBLISHED: 2020-02-22
graph_realtime.php in Cacti 1.2.8 allows remote attackers to execute arbitrary OS commands via shell metacharacters in a cookie, if a guest user has the graph real-time privilege.
CVE-2020-9039
PUBLISHED: 2020-02-22
Couchbase Server 4.x and 5.x before 6.0.0 has Insecure Permissions for the projector and indexer REST endpoints (they allow unauthenticated access).
CVE-2020-8860
PUBLISHED: 2020-02-22
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Samsung Galaxy S10 Firmware G973FXXS3ASJA, O(8.x), P(9.0), Q(10.0) devices with Exynos chipsets. User interaction is required to exploit this vulnerability in that the target must answer a phone call. T...
CVE-2020-8861
PUBLISHED: 2020-02-22
This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of D-Link DAP-1330 1.10B01 BETA Wi-Fi range extenders. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of HNAP login requests. The issue ...
CVE-2020-8862
PUBLISHED: 2020-02-22
This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of D-Link DAP-2610 Firmware v2.01RC067 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of passwords. The issue results from the ...