Vulnerabilities / Threats // Vulnerability Management
02:00 PM
Connect Directly

XFINITY Security System Flaw Allows Sneak Attacks By Jamming Radio Frequency

Rapid7 Researcher finds that when communication between base station and sensors is disrupted, alarm system continues to think it is armed.

The prognosticators promised us lots of smart home vulnerabilities in 2016 and it only took a couple of days for the first disclosure to come out of the woodwork. A researcher with Rapid7 today reported a flaw in Comcast XFINITY's Home Security System that allows attackers to jam the radio frequency the system the system uses without ever triggering an alert to the home owner.

According to Phil Bosco, security consultant for Rapid7, his team found that all it takes to open windows or doors without detection is interrupting the 2.4 GHz radio frequency band used by the base station to communicate with window and door sensors. Rather than alerting the user to a change in state of the security system, the ZigBee-based system continues to report that the sensors are intact, doors are closed, and no motion is detected -- while any movement in the doors remains unmonitored.

This is a huge black spot on the peace of mind that security system users get when out of the house and checking their phone for updates on the protection of their homes. Attackers would be able to slip in and out of a protected building by using one of a couple of simple attack techniques to carry this out, says Tod Beardsley, security research manager for Rapid7.

"There are any number of techniques that could be used to cause interference or deauthentication of the underlying ZigBee-based communications protocol, such as commodity radio jamming equipment and software -based deauthentication attacks on the ZigBee protocol itself," Beardsley wrote in a blog posted today about the research.

His team initially carried out the testing on this system by putting tin foil around a window/door sensor while the system was armed, and then removing the magnet from the sensor to simulate a radio jamming attack.

"Once the magnet is removed from the sensor, the sensor was unwrapped and placed within a few inches from the base station hub that controls the alarm system," Beardsley says. "The system continued to report that it is in armed state. The amount of time it takes for the sensor to reestablish communications with the base station and correctly report is in an open state can range from several minutes to up to three hours."

The last detail is perhaps one of the most disconcerting. The system has no time limit on a communication interruption before it reports a change in state, and even when communication is back up, there's no consistent way for the base station and sensor to sync back up because the system already thinks nothing has changed.

Unfortunately, the flaw currently has "no practical mitigations," according to the researchers. Rapid7 initially disclosed this issue to the vendor in early November and to CERT later that month.


Ericka Chickowski specializes in coverage of information technology and business innovation. She has focused on information security for the better part of a decade and regularly writes about the security industry as a contributor to Dark Reading.  View Full Bio

Comment  | 
Print  | 
More Insights
Newest First  |  Oldest First  |  Threaded View
User Rank: Ninja
1/10/2016 | 11:45:27 AM
2.4Ghz is such a commonly used frequency and so easy to disrupt. (IE: Baby Monitors, Drones, Cameras, Routers..) A simple wireless assessment in any given area immediately shows multiple overlapping channels in this range. Although less common this also occurs in the 5Ghz range as well. The FCC should reserve higher band frequencies for security systems or XFINITY should just utilize GSM networks. Even most modern cordless phones take advantage of DECT 6.0. Why is this not being used in some way for communication from the sensor to base?
Register for Dark Reading Newsletters
White Papers
Current Issue
5 Security Technologies to Watch in 2017
Emerging tools and services promise to make a difference this year. Are they on your company's list?
Flash Poll
New Best Practices for Secure App Development
New Best Practices for Secure App Development
The transition from DevOps to SecDevOps is combining with the move toward cloud computing to create new challenges - and new opportunities - for the information security team. Download this report, to learn about the new best practices for secure application development.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
Published: 2015-10-15
The Direct Rendering Manager (DRM) subsystem in the Linux kernel through 4.x mishandles requests for Graphics Execution Manager (GEM) objects, which allows context-dependent attackers to cause a denial of service (memory consumption) via an application that processes graphics data, as demonstrated b...

Published: 2015-10-15
netstat in IBM AIX 5.3, 6.1, and 7.1 and VIOS 2.2.x, when a fibre channel adapter is used, allows local users to gain privileges via unspecified vectors.

Published: 2015-10-15
Cross-site request forgery (CSRF) vulnerability in eXtplorer before 2.1.8 allows remote attackers to hijack the authentication of arbitrary users for requests that execute PHP code.

Published: 2015-10-15
Directory traversal vulnerability in QNAP QTS before 4.1.4 build 0910 and 4.2.x before 4.2.0 RC2 build 0910, when AFP is enabled, allows remote attackers to read or write to arbitrary files by leveraging access to an OS X (1) user or (2) guest account.

Published: 2015-10-15
Cisco Application Policy Infrastructure Controller (APIC) 1.1j allows local users to gain privileges via vectors involving addition of an SSH key, aka Bug ID CSCuw46076.

Dark Reading Radio
Archived Dark Reading Radio
In past years, security researchers have discovered ways to hack cars, medical devices, automated teller machines, and many other targets. Dark Reading Executive Editor Kelly Jackson Higgins hosts researcher Samy Kamkar and Levi Gundert, vice president of threat intelligence at Recorded Future, to discuss some of 2016's most unusual and creative hacks by white hats, and what these new vulnerabilities might mean for the coming year.