Team of French Cops from Cybercrime Fighting Center (C3N) takedown the Retadup worm command & control servers to block the further infection and remotely wipe the malware from 850,000 windows computers.
Retadup is a malicious worm that can infect the vulnerable windows computers and take control of it to add into its botnet network, additionally, it installs additional malware payloads on compromised computers.
Avast played a big role in this action by helping them with the Retadup intelligence details and shared the technique to wipe the Retadup worm from the infected victim’s computer.
C3N completely dismantled the malicious command & control server that operated by the Retadup malware authors and replaced with the disinfected C2 server.
“The disinfection server responded to incoming bot requests with a specific response that caused connected pieces of the malware to self-destruct.”
Researchers believed that the Retadup C2 server mostly resides in French and the design flaw in C&C protocol allows them to easily bypass the network and replace with the legitimate server.
Malware authors mostly use this Retadup worn to set up a cryptocurrency miner in victims computer and generate a passive income.
Later year cryptocurrency miner same RETADUP Worm Goes Polymorphic to Evade Detection by Security Scanners.
Legal Precedence to Take Down the C2 server
Since the botnet control C2 infrastructure believed to be located in France, In Mach, Avast decided to contact the French National Gendarmerie and suggested them to taking over a C&C server by abusing the C&C design flaw.
In July 2019, French National Gendarmerie received an order from the court to proceed to disinfection.
Later, C3N replaced the malicious C&C server with a prepared disinfection server that made connected instances of Retadup self-destruct.
According to the Avast report, “Some parts of the C&C infrastructure were also located in the US. The Gendarmerie alerted the FBI who took them down, and on July 8 the malware authors no longer had any control over the malware bots.”
Most of the Retadup malware targeted victims computer running with Windows 7 and 85% of victims had no third-party antivirus software installed and some of them are disabled which all are completely vulnerable to propagate the other systems in the network.
Windows users are highly recommended to install the Antivirus software and keep the systems up to date by applying the necessary patch to protect from the cyber threats.