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.

Attacks/Breaches

10/17/2013
01:55 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

DDoS Attack Used 'Headless' Browsers In 150-Hour Siege

Distributed denial-of-service attack employed a browser app toolkit to simulate Web visitors accessing the victim's website

"Headless" browsers pummeled a trading platform's website this past week in a rare form of a distributed denial-of-service (DDoS) attack that lasted for 150 hours.

The attack employed some 180,000 IP addresses -- and as of today continues to rebound in smaller pockets -- according to cloud-based DDoS mitigation service provider Incapsula, which discovered and mitigated the massive attack for its customer.

The company declined to name the targeted organization, only saying it was a trading platform and that the attackers were likely motivated for competitive reasons. "The order of magnitude was significant," says Marc Gaffan, co-founder of Incapsula. "No one has 180,000 IPs at their disposal unless it's an amalgamation of separate botnets they are using interchangeably. This was a sophisticated and thought-out process."

DDoS attacks increasingly have moved up the stack to the application layer, mainly for more targeted purposes, such as disrupting transactions or access to databases. According to new data from Arbor Networks, DDoS attacks, in general, are getting more powerful, but their duration is declining: The average DDoS attack size thus far is 2.64 Gbps for the year, an increase of 78 percent from 2012, and some 87 percent of attacks last less than one hour.

That makes the recent headless browser attack even more unusual, given that its duration was so long. "That's pretty long. Obviously, someone was upset at them," says Marc Eisenbarth, manager of research for Arbor.

[DDoS attack sizes are rising even as the duration of the attacks grows shorter, according to Arbor Networks. See DDoS Attacks Grow Shorter But Pack More Punch.]

The attack also was unusual in that it employed a version of the Phantom JS headless browser toolkit, which is a Web app developer's tool for testing and simulating user browsing of an application. "This was the first time we saw this technology in a DDoS attack," Gaffan says. "It mimics human behavior so effectively that it's a challenge for mitigation services to deal with."

Phantom JS is basically a test tool that uses a bare-bones or "headless" browser -- no buttons, address bar, etc. -- with an API so programmers can test-run and automate their apps. "They can do a load test to websites simulating browser behavior and run JavaScript and accept cookies," for example, Gaffan says.

Arbor's Eisenbarth says he rarely sees Phantom JS being abused the way Incapsula has described this DDoS attack on its customer. "We don't see Phantom JS as much. What we do see are attackers creating hidden [Internet Explorer] browsers that actually are full-function browsers and are even more sophisticated at bypassing detection mechanisms," Eisenbarth says.

The attackers also employed some 861 different variants of the headless browser and were generating some 700 million hits per day on the targeted website, according to Incapsula. "It's really an evasion technique. We try to catch what they are doing, and they try to evade us," Gaffan says. "Our job is to filter out the good guys [legitimate visitors] and let them pass ... the site still needs to operate. And then keep the bad traffic out."

Dan Holden, director of security research at Arbor Networks, says these Layer 7 DDoS attacks take more effort to execute. "There's got to be something financial" motivating the attackers, he says. "These are more common when you've got very focused and targeted attacks."

Incapsula's Gaffan says application-layer DDoS attacks are becoming more popular and often accompany network-layer attacks. "That leaves you scrambling on all fronts," he says. "An application-layer attack is easier to perpetrate because it requires less resources, but you need expertise" to pull it off, he says.

The victim organization's business in the end suffered little impact since Incapsula was able to mitigate the attack, he says. But the DDoS hasn't disappeared yet, either: "It started last week, and to some extent, it's still ongoing," Gaffan says. "There's an ongoing process [by the attackers] of updating and changing" the headless browsers in the attack, he says.

Have a comment on this story? Please click "Add Your Comment" 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
COVID-19: Latest Security News & Commentary
Dark Reading Staff 9/25/2020
Hacking Yourself: Marie Moe and Pacemaker Security
Gary McGraw Ph.D., Co-founder Berryville Institute of Machine Learning,  9/21/2020
Startup Aims to Map and Track All the IT and Security Things
Kelly Jackson Higgins, Executive Editor at Dark Reading,  9/22/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Special Report: Computing's New Normal
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
How IT Security Organizations are Attacking the Cybersecurity Problem
How IT Security Organizations are Attacking the Cybersecurity Problem
The COVID-19 pandemic turned the world -- and enterprise computing -- on end. Here's a look at how cybersecurity teams are retrenching their defense strategies, rebuilding their teams, and selecting new technologies to stop the oncoming rise of online attacks.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-15208
PUBLISHED: 2020-09-25
In tensorflow-lite before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1 and 2.3.1, when determining the common dimension size of two tensors, TFLite uses a `DCHECK` which is no-op outside of debug compilation modes. Since the function always returns the dimension of the first tensor, malicious attackers can ...
CVE-2020-15209
PUBLISHED: 2020-09-25
In tensorflow-lite before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1 and 2.3.1, a crafted TFLite model can force a node to have as input a tensor backed by a `nullptr` buffer. This can be achieved by changing a buffer index in the flatbuffer serialization to convert a read-only tensor to a read-write one....
CVE-2020-15210
PUBLISHED: 2020-09-25
In tensorflow-lite before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1 and 2.3.1, if a TFLite saved model uses the same tensor as both input and output of an operator, then, depending on the operator, we can observe a segmentation fault or just memory corruption. We have patched the issue in d58c96946b and ...
CVE-2020-15211
PUBLISHED: 2020-09-25
In TensorFlow Lite before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1 and 2.3.1, saved models in the flatbuffer format use a double indexing scheme: a model has a set of subgraphs, each subgraph has a set of operators and each operator has a set of input/output tensors. The flatbuffer format uses indices f...
CVE-2020-15212
PUBLISHED: 2020-09-25
In TensorFlow Lite before versions 2.2.1 and 2.3.1, models using segment sum can trigger writes outside of bounds of heap allocated buffers by inserting negative elements in the segment ids tensor. Users having access to `segment_ids_data` can alter `output_index` and then write to outside of `outpu...