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.

Analytics //

Security Monitoring

5/18/2013
08:19 AM
50%
50%

Large Attacks Hide More Subtle Threats In DDoS Data

While distributed denial-of-service attacks topping 100 Gbps garner the headlines, they are not the threat that should worry most companies

The massive avalanche of data in March that crashed down on Spamhaus, the maintainer of a number of spam blacklists, made headlines as the largest distributed denial-of-service (DDoS) attack witnessed to date.

Along with the ongoing campaign against financial institutions by a group of attackers calling themselves the Cyber Fighters of Izz ad-din Al Qassam, the attacks drove the bandwidth of the average DDoS to nearly 50 Gbps during the first quarter of 2013, a sevenfold increase over the past three months of 2012, according to a quarterly report by DDoS mitigation firm Prolexic.

Yet those large attacks are not the most significant denial-of-service (DoS) threat for most companies, according to DDoS mitigation experts.

"The big gigabit, the big DNS reflection attacks -- those get all the press, but the ones that are devastating are the ones that knock the application down," says Vann Abernethy, senior product manager for NSFOCUS, a Beijing-based DDoS-mitigation and network-security firm.

While approximately three-quarters of all DoS attacks are bandwidth-clogging floods of network packets, the remaining quarter are application-layer attacks. These attacks can cause far more chaos for companies, taking servers down and requiring greater cleanup efforts than simple infrastructure attacks.

The situation is made more complicated for defenders by the fact that attackers increasingly use data floods to hide low-volume application-layer attacks. Companies need to be able to watch for the attacks, also known as Layer-7 attacks, and be able to detect the trickle of attack packets inside of the much larger infrastructure attacks, says David Fernandez, information security manager for Prolexic's PLXsert security team. Prolexic typically sees about 10 to 15 percent of packet floods hiding a more insidious attack on the target's application.

"Companies should have the ability to isolate the application attacks from the volumetric DDoS," Fernandez says. "There is a pattern in there, and isolating that should be a priority."

The attacks can be differentiated at the packet level, so defending against application-layer attacks means culling as much of the larger attack from the traffic and then inspecting the remaining packets to find those that match the ongoing attack. Needless to say, defending against application-layer attacks takes time and effort, says Dan Holden, director of security research at Arbor Networks, an anti-DDoS technology provider.

"DDoS defense is not a plug-and-play technology," he says. "It is an active defense model. From an application-defense standpoint, you can do things at the application level itself to strengthen the application or disable certain features temporarily."

[Referring to the attacks as "a call to action for the Internet community as a whole," security groups urge organizations to lock down any open DNS resolvers. See Spamhaus DDoS Spotlights DNS Server Security Challenge.]

While companies can rely on service providers or their ISPs to help mitigate infrastructure attacks, application-layer attacks are a different situation, says Holden. The attacks are not a network problem but a business problem, and no one understands a company's business like it does, he says.

"You know more about your application than your ISP is going to, so when it comes to defense, your security team is going to be the best-suited," Holden says.

Finally, companies should not discount the possibility of a massive attack. While high-bandwidth attacks are currently the hallmark of the Cyber Fighters of Izz ad-din Al Qassam, the group is not the only one aiming high. Other groups have managed to exceed the 100-Gbps mark as well, Prolexic's Fernandez says. In the first quarter, nearly a dozen attacks topped 100 Gbps. The biggest attack that Prolexic has witnessed was an attack in April that topped 160 Gbps.

Companies need to do a risk assessment to make sure they can withstand attacks on their businesses, Fernandez says. Companies should expect that they will be targeted with an attack of tens of gigabits per second as well as an application-layer attack, and make sure they are prepared to handle the incident.

"The best measure is to validate what the risk is of certain of your business, and make sure that you can allocate for that," 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. Veteran technology journalist of more than 20 years. Former research engineer. Written for more than two dozen publications, including CNET News.com, Dark Reading, MIT's Technology Review, Popular Science, and Wired News. Five awards for journalism, including Best Deadline ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 10/30/2020
'Act of War' Clause Could Nix Cyber Insurance Payouts
Robert Lemos, Contributing Writer,  10/29/2020
6 Ways Passwords Fail Basic Security Tests
Curtis Franklin Jr., Senior Editor at Dark Reading,  10/28/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
How to Measure and Reduce Cybersecurity Risk in Your Organization
In this Tech Digest, we examine the difficult practice of measuring cyber-risk that has long been an elusive target for enterprises. Download it today!
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-2020-5425
PUBLISHED: 2020-10-31
Single Sign-On for Vmware Tanzu all versions prior to 1.11.3 ,1.12.x versions prior to 1.12.4 and 1.13.x prior to 1.13.1 are vulnerable to user impersonation attack.If two users are logged in to the SSO operator dashboard at the same time, with the same username, from two different identity provider...
CVE-2020-15703
PUBLISHED: 2020-10-31
There is no input validation on the Locale property in an apt transaction. An unprivileged user can supply a full path to a writable directory, which lets aptd read a file as root. Having a symlink in place results in an error message if the file exists, and no error otherwise. This way an unprivile...
CVE-2020-5991
PUBLISHED: 2020-10-30
NVIDIA CUDA Toolkit, all versions prior to 11.1.1, contains a vulnerability in the NVJPEG library in which an out-of-bounds read or write operation may lead to code execution, denial of service, or information disclosure.
CVE-2020-15273
PUBLISHED: 2020-10-30
baserCMS before version 4.4.1 is vulnerable to Cross-Site Scripting. The issue affects the following components: Edit feed settings, Edit widget area, Sub site new registration, New category registration. Arbitrary JavaScript may be executed by entering specific characters in the account that can ac...
CVE-2020-15276
PUBLISHED: 2020-10-30
baserCMS before version 4.4.1 is vulnerable to Cross-Site Scripting. Arbitrary JavaScript may be executed by entering a crafted nickname in blog comments. The issue affects the blog comment component. It is fixed in version 4.4.1.