Arrests Tied to Citadel, Dridex Malware
Authorities in Europe have arrested alleged key players behind the development and deployment of sophisticated banking malware, including Citadel and Dridex. The arrests involved a Russian national and a Moldovan man, both of whom were traveling or residing outside of their native countries and are now facing extradition to the United States.
cuffedLast week, a 30-year-old from Moldova who was wanted by U.S. authorities was arrested in Paphos — a coastal vacation spot in Cyprus where the accused was reportedly staying with his wife. A story in the Cyprus Mail has few other details about the arrest, other than to say authorities believe the man was responsible for more than $3.5 million in bank fraud using a PC.
Sources close to the investigation say the man is a key figure in an organized crime gang responsible for developing and using a powerful banking Trojan known as “Dridex” (a.k.a. Cridex, Bugat). The Dridex gang is thought to have spun off from the “Business Club,” an Eastern European organized cybercrime gang accused of stealing more than $100 million from banks and businesses worldwide.
In June 2014, the U.S. Justice Department joined multiple international law enforcement agencies and security firms in taking down the Business Club’s key asset: The Gameover ZeuS botnet, an ultra-sophisticated, global crime machine that infected upwards of a half-million PCs and was used in countless cyberheists. Dridex would first emerge in July 2014, a month after the Gameover Zeus botnet was dismantled.
Separately, the press in Norway writes about a 27-year-old Russian man identified only as “Mark” who was reportedly arrested in the Norwegian town of Fredrikstad at the request of the FBI. The story notes that American authorities believe Mark is the software developer behind Citadel, a malware-as-a-service product that played a key role in countless cyberheists against American and European small businesses.
For example, Citadel was thought to have been the very same malware used to steal usernames and passwords from a Pennsylvania heating and air conditioning vendor; those same stolen credentials were reportedly leveraged in the breach that resulted in the theft of nearly 40 million credit cards from Target Corp. in November and December of 2013.
The Norwegian newspaper VG writes that Mark has been held under house arrest for the past 11 months, while the FBI tries to work out his extradition to the United States. His detention is being fought by Russia, which is naturally opposed to the treatment he may receive in the United States and says the evidence against Mark is scant.
According to VG, the U.S. Justice Department believes Mark is none other than “Aquabox,” the nickname chosen by the proprietor of the Citadel malware, which was created based off of the source code for the ZeuS Trojan malware. Citadel was sold and marketed as a service that let buyers and users interact with the developer and one another, to solicit feedback on how to fix bugs in the malware program, and to request new features in the malware going forward.
For a full translation of the original Citadel sales pitch as penned by Aquabox in 2011, see this link (PDF). For a full translated version of the VG story on Mark, see this PDF (thanks to KrebsOnSecurity reader Jeevan Sivagnanasuntharam for helping with the translation). VG notes that Mark continues to maintain his innocence. [Side note: The Citadel malware has for years had in its code a dig directed at the author of this blog: Included in the guts of the Trojan is the text string, “Coded by BRIAN KREBS for personal use only. I love my job & wife.” Needless to say, the second part of that statement is true, but Citadel was not coded by this Brian Krebs.]
A text string inside of the Citadel trojan. Source: AhnLab
Ars Technica carries an interesting piece about Deniss Calovskis, a Latvian man who was arrested in February and extradited to the United States for his role in creating the Gozi virus, another powerful malware family that has been used in countless cyberheists. The 30-year-old Calovskis long maintained his innocence, but ultimately acknowledged his role in a guilty plea entered in a federal court in Manhattan last week.
In August 2013, Calovskis denied being associated with Gozi, and told Latvian a television news station that he was “like a hostage in this situation. I don’t know about the Gozi virus. I haven’t helped any schemers to get money and I haven’t received any,” he told reporters. According to Reuters, Calovskis changed his tune last week.
“I knew what I was doing was against the law,” he reportedly told the court.
Finally, Finnish authorities are holding a Russian man named Maxim Senakh who is accused of committing malware crimes in the United States. Russian news agency RT says the Russian Foreign Ministry has denounced Senakh’s detention as an “illegal practice” and a “witchhunt.” He was reportedly detained on Aug. 8, 2015.
The various media stories in the European press about Senakh’s arrest say he is wanted for cyber crimes allegedly committed against a victim in Minnesota, but beyond that there are few details about the reason behind his arrest. U.S. authorities are currently seeking his extradition to the United States.
