Attacks/Breaches
2/28/2013
11:08 AM
Connect Directly
RSS
E-Mail
50%
50%

MiniDuke Espionage Malware Uses Twitter To Infect PCs

Online espionage campaign sends malicious PDF documents to victims, and the infected PCs use Twitter to install malware that can copy and delete files.

Who Is Anonymous: 10 Key Facts
Who Is Anonymous: 10 Key Facts
(click image for larger view and for slideshow)
Security researchers have spotted an online espionage campaign that infects targeted systems with malware that's only 20KB in size and controlled via Twitter accounts.

According to Russian security firm Kaspersky Lab and Budapest-based CrySyS Lab, which both discovered the attack code -- named MiniDuke -- the campaign appears to remain active, because recovered malware used by attackers was created as recently as Feb. 20.

"To compromise the victims, the attackers used extremely effective social engineering techniques which involved sending malicious PDF documents to their targets," according to an overview of MiniDuke published by Kaspersky Lab. "The PDFs were highly relevant and well-crafted content that fabricated human rights seminar information and Ukraine's foreign policy and NATO membership plans."

[ Malware is everywhere, but here's how one attacker was shut down. Read Virut Malware Botnet Torpedoed By Security Researchers. ]

The malicious PDFs exploited a bug, since patched, in Adobe Reader versions 9, 10 and 11, which allowed the attackers to bypass Reader's sandbox and install a small dropper, or downloader, onto the PC that gives an attackers a backdoor for remotely accessing the now-compromised system.

The attack used same the zero-day vulnerability in Adobe Reader discovered by FireEye and first publicly detailed on Feb. 12, after the security firm spotted malicious PDFs disguised as a Turkish visa application. But it's not clear if MiniDuke was launched by the same group, or whether it just purchased a crimeware toolkit from the same vendor that included an exploit for the vulnerability.

Interestingly, each MiniDuke backdoor is custom coded to work only on the targeted machine, meaning if it's moved to a different PC it won't execute. "This downloader is unique per system and contains a customized backdoor written in Assembler," said Kaspersky Lab. "When loaded at system boot, the downloader uses a set of mathematical calculations to determine the computer's unique fingerprint, and in turn uses this data to uniquely encrypt its communications later."

"The backdoor is written in 'old school' assembler and is tiny by current standards -- only 20 KB," according to "The MiniDuke Mystery: PDF 0-day Government Spy Assembler 0x29A Micro Backdoor" research report released Wednesday by Kaspersky and CrySys Lab. "This is most unusual for modern malware, which can be several megabytes in size."

After infecting a PC, the attack code first checks to see if it's infected a desired system. If so, then the PC will surreptitiously contact Twitter accounts created by MiniDuke command-and-control (C&C) servers, which contain tweets which list encrypted URLs -- in the form of hash tags -- to which the infected PC can connect to receive further instructions. These instructions are received in the form of GIF files that are "disguised as pictures that appear on a victim's machine," according to Kaspersky Lab, and enable the downloader to then grab another executable -- one recovered sample was a 300KB file disguised as a GIF -- from a server in either Panama or Turkey. This larger piece of malware then serves as a platform for conducting cyber-espionage, including not just copying and removing files, but also running new malware and spreading malware onto other systems connected to the same network.

The malware includes backup capabilities in the event that Twitter can't be reached or the malnet's Twitter accounts get deleted, such as using Google to search for encrypted URL strings. "This model is flexible and enables the operators to constantly change how their backdoors retrieve further commands or malcode as needed," said the Kaspersky report.

The malware's creators have tried to make their attack code difficult to detect, in part by using disguised JavaScript. "The available malware samples are highly obfuscated, and compiled by a polymorphic compiler. The attackers were able to produce new variants with only a few minutes difference between compile times. Therefore, the number of distinct samples could be very large," said a blog post from the CrySyS lab, which also released a report that includes more detailed information on the malware, as well as tips for how to spot PCs that have been infected.

Based on the logs of command-and-control servers accessed by researchers, MiniDuke has been used only in a small number of targeted attacks. To date, just 59 infected systems have been found in 23 countries, including the United States and much of Europe, as well as Brazil, Israel, Japan, Romania, the Russian Federation and Ukraine.

Attend Interop Las Vegas, May 6-10, and attend the most thorough training on Apple Deployment at the NEW Mac & iOS IT Conference. Use Priority Code DIPR02 by March 2 to save up to $500 off the price of Conference Passes. Join us in Las Vegas for access to 125+ workshops and conference classes, 350+ exhibiting companies, and the latest technology. Register for Interop today!

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
PJS880
50%
50%
PJS880,
User Rank: Ninja
3/15/2013 | 5:10:10 PM
re: MiniDuke Espionage Malware Uses Twitter To Infect PCs
This sounds like one bad little piece of malware, small in size and packing a punch. There seems to be a trend that I am reading about as far as the way these breeches are occurring and that is through the user clicking on some piece of malware, weather it be a .pdf file, email, or a link. I think the knowledge to walk away with here is donGÇÖt open it, once again; of you donGÇÖt know the sender or where it came from. Very creative going in through the Twitter hash tags. Does the infected system have to already have some associated Twitter account or does that not even matter?

Paul Sprague
InformationWeek Contributor
Register for Dark Reading Newsletters
White Papers
Flash Poll
Current Issue
Cartoon
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2014-0972
Published: 2014-08-01
The kgsl graphics driver for the Linux kernel 3.x, as used in Qualcomm Innovation Center (QuIC) Android contributions for MSM devices and other products, does not properly prevent write access to IOMMU context registers, which allows local users to select a custom page table, and consequently write ...

CVE-2014-2627
Published: 2014-08-01
Unspecified vulnerability in HP NonStop NetBatch G06.14 through G06.32.01, H06 through H06.28, and J06 through J06.17.01 allows remote authenticated users to gain privileges for NetBatch job execution via unknown vectors.

CVE-2014-3009
Published: 2014-08-01
The GDS component in IBM InfoSphere Master Data Management - Collaborative Edition 10.0 through 11.0 and InfoSphere Master Data Management Server for Product Information Management 9.0 and 9.1 does not properly handle FRAME elements, which makes it easier for remote authenticated users to conduct ph...

CVE-2014-3302
Published: 2014-08-01
user.php in Cisco WebEx Meetings Server 1.5(.1.131) and earlier does not properly implement the token timer for authenticated encryption, which allows remote attackers to obtain sensitive information via a crafted URL, aka Bug ID CSCuj81708.

CVE-2014-3534
Published: 2014-08-01
arch/s390/kernel/ptrace.c in the Linux kernel before 3.15.8 on the s390 platform does not properly restrict address-space control operations in PTRACE_POKEUSR_AREA requests, which allows local users to obtain read and write access to kernel memory locations, and consequently gain privileges, via a c...

Best of the Web
Dark Reading Radio