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.


08:51 PM
Connect Directly

'Comfoo' APT Cyberespionage Campaign Exposed

Trojan used in the breach of RSA in 2010 remains active and prolific in targeted attacks

LAS VEGAS -- BLACK HAT USA -- A remote access Trojan (RAT) that was used in the big RSA data breach three years ago remains active and prolific in targeted attacks against government ministries, telecommunications providers, mineral exploration firms, technology firms, and media outlets, mainly in Asia and some in the U.S.

Click here for more of Dark Reading's Black Hat articles.

Malware experts Joe Stewart and Don Jackson of Dell Secureworks gained access to the command-and-control (C&C) infrastructure of the so-called Comfoo Trojan -- a rare feat in most advanced persistent threat (APT) attacks -- and also found proof of how widespread the lesser known malware really is: The researchers discovered 64 different targeted attack campaigns using the RAT, as well as some 200 variants of the Trojan.

Comfoo has been associated with one of China's largest cyberespionage organizations known as the Beijing Group, and the attacks discovered by Secureworks operate on the same infrastructure as the group. "But it may or may not be the same persons at the other end of the computers. They may just be sharing the same infrastructure," Stewart says.

The RAT has been in development since at least 2006, but has managed to fly mostly under the radar, according to the researchers, who published a report on Comfoo this week.

Japan and India were the main targets, as well as Taiwan and South Korea. The researchers also found infected machines in the U.S. and Europe.

Despite the Comfoo Trojan's longevity and regular revamping, it's one of the lesser-publicized RATs, according to Stewart, mainly because it has kept a relatively low profile. "It's still under the radar, it would seem. There have not been a lot of public reports" about it, he says. "But we saw all of this infrastructure, all of these tags and campaigns and all of this malware.

"There's a lot of it being used and a lot more targets than people suspect," says Stewart, who is director of malware research for Dell Secureworks' Counter Threat Unit. "The amount of work this team must be doing to maintain this Trojan and all this infrastructure" is significant, he says.

Stewart was able to access Comfoo's C&C servers because back-end servers didn't require authentication and because he was able to crack the infrastructure's encryption. He figured out the protocol and static encryption key that was hard-coded into Comfoo binary code, and got a bird's-eye view of victim machines dialing home to the Trojan's C&C relay servers. Secureworks would not reveal the names of the victim organizations, but all have been alerted about the attacks, Stewart says.

While the researchers were unable to see the actual data being lifted from the victims, they witnessed Comfoo accessing system and network information, logging keystrokes, uploading files, downloading files, taking screenshots, and opening a command shell.

One major attack campaign waged by the Comfoo gang was in 2012, hitting more than 20 Japanese government ministries, universities, municipal governments, trade organizations, media outlets, think-tanks, and industrial machinery manufacturers.

In an interesting twist, Comfoo also targeted the networks of audioconferencing and videoconferencing companies. Stewart says it's possible that they are trying to steal intellectual property here on this technology, but more likely that they are gathering intel on these companies for spying purposes on other targets via the providers' audio- and videoconferencing systems.

The full Secureworks report is available here.

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
Newest First  |  Oldest First  |  Threaded View
Register for Dark Reading Newsletters
White Papers
Cartoon Contest
Current Issue
2020: The Year in Security
Download this Tech Digest for a look at the biggest security stories that - so far - have shaped a very strange and stressful year.
Flash Poll
Assessing Cybersecurity Risk in Today's Enterprises
Assessing Cybersecurity Risk in Today's Enterprises
COVID-19 has created a new IT paradigm in the enterprise -- and a new level of cybersecurity risk. This report offers a look at how enterprises are assessing and managing cyber-risk under the new normal.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
PUBLISHED: 2021-01-25
An XML external entity (XXE) injection vulnerability was discovered in the Nutch DmozParser and is known to affect Nutch versions < 1.18. XML external entity injection (also known as XXE) is a web security vulnerability that allows an attacker to interfere with an application's processing of XML ...
PUBLISHED: 2021-01-25
When handler-router component is enabled in servicecomb-java-chassis, authenticated user may inject some data and cause arbitrary code execution. The problem happens in versions between 2.0.0 ~ 2.1.3 and fixed in Apache ServiceComb-Java-Chassis 2.1.5
PUBLISHED: 2021-01-22
Pepperl+Fuchs Comtrol IO-Link Master in Version 1.5.48 and below is prone to an authenticated reflected POST Cross-Site Scripting
PUBLISHED: 2021-01-22
Pepperl+Fuchs Comtrol IO-Link Master in Version 1.5.48 and below is prone to an authenticated blind OS Command Injection.
PUBLISHED: 2021-01-22
Pepperl+Fuchs Comtrol IO-Link Master in Version 1.5.48 and below is prone to a NULL Pointer Dereference that leads to a DoS in discoveryd