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

Guerrilla Storage

Hackers could use your computers to house their data, Symantec researchers say

If you find a few megabytes of data in your buffers that don't belong to you, beware: You may have been infected by a storage-hungry parasite.

In its blog this week, Symantec Corp. (Nasdaq: SYMC) is warning users of an exploit called "parasitic storage," in which hackers store small amounts of data on hundreds of machines.

"A tiny bit of RAM on a large number of computers can be used to store secret data that an attacker wants to hide, while a lot of information can be stored on some servers at the risk of being found and removed," Symantec says.

The concept of parasitic storage is not new, and by itself it creates very little problem for users, since the storage load is usually diffused across the network in buffers or in transit, notes Javier Santoyo, manager of development at Symantec.

"But a problem may come if the data stored in the buffers is a trigger for malware on a machine," Santoyo says. "We haven't seen it yet, but there is a potential."

Parasitic storage is not just a way to save hackers a few bucks on a hard drive. In many cases, it's used to store sensitive or illegal data. By diffusing the data across many machines in a configuration controlled only by the attacker, a cyber criminal can "keep" incriminating information that can't be accessed by others.

"If the computer is powered off or unplugged, the data is lost forever," Symantec notes. "Although losing data this easily may be seen as a drawback to some, it's an advantage when the attacker wants plausible deniability. As far as anyone -- such as parents or law enforcement -- can tell, the data never even existed."

Unlike botnets, parasitic storage can make use of legitimate storage in network devices, without taking over or compromising the infected machine. "The attacker would have to compromise at least one system to make it work -- bad guys never use their own equipment for this type of attack -- but after that, they are basically using available memory on the network," Santoyo says. "It's very hard to detect, because it all looks like valid data."

"Another method of [parasitic storage] is to combine stenography (encoding text within images) with free image hosting," Symantec says. "On the Internet, there are many sites that allow users to upload full-size images, and even more that let users upload small avatars. An attacker can make use of thousands of these sites to hide a considerable amount of data.

"It may even be possible to encode the location of the next chunk of data in the current chunk, which means that only a small amount of data would have to be stored online," Symantec explains. "As long as this data is encrypted and spread out enough, it may not be possible to determine that the data even exists, let alone find it."

Santoyo says parasitic storage is "currently a low level threat" and Symantec is not currently developing any tools to stop it. Users can flush the hitchhiking data by recycling or rebooting their machines, but such rebooting is often difficult on devices such as servers, which run on a 24x7 basis, he notes.

— Tim Wilson, Site Editor, Dark Reading

Tim Wilson is Editor in Chief and co-founder of Dark Reading.com, UBM Tech's online community for information security professionals. He is responsible for managing the site, assigning and editing content, and writing breaking news stories. Wilson has been recognized as one ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
Stop Defending Everything
Kevin Kurzawa, Senior Information Security Auditor,  2/12/2020
Small Business Security: 5 Tips on How and Where to Start
Mike Puglia, Chief Strategy Officer at Kaseya,  2/13/2020
Architectural Analysis IDs 78 Specific Risks in Machine-Learning Systems
Jai Vijayan, Contributing Writer,  2/13/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
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-2020-9016
PUBLISHED: 2020-02-16
Dolibarr 11.0 allows XSS via the joinfiles, topic, or code parameter, or the HTTP Referer header.
CVE-2020-9013
PUBLISHED: 2020-02-16
Arvato Skillpipe 3.0 allows attackers to bypass intended print restrictions by deleting <div id="watermark"> from the HTML source code.
CVE-2020-9007
PUBLISHED: 2020-02-16
Codoforum 4.8.8 allows self-XSS via the title of a new topic.
CVE-2020-9012
PUBLISHED: 2020-02-16
A cross-site scripting (XSS) vulnerability in the Import People functionality in Gluu Identity Configuration 4.0 allows remote attackers to inject arbitrary web script or HTML via the filename parameter.
CVE-2019-20456
PUBLISHED: 2020-02-16
Goverlan Reach Console before 9.50, Goverlan Reach Server before 3.50, and Goverlan Client Agent before 9.20.50 have an Untrusted Search Path that leads to Command Injection and Local Privilege Escalation via DLL hijacking.