Cerber, one of the most prevalent ransomware families this year, is now using random extensions for encrypted files and is now able to kill the processes of various database servers, researchers reveal.
The Cerber ransomware, which was accounting for a quarter of ransomware detections three months ago, adopted improved key generation in early August, and was estimated to have generated $2.3 million in annual revenue. Historically, the threat has been distributed through exploit kits and spam emails, but also by other malware.
At the beginning of September, Cerber was seen being distributed by Betabot, and the latest major variant of the malware emerged soon after. Dubbed Cerber 3.0, it was using a brand new extension for the encrypted files (.cerber3) as well as a modified ransom note and reduced ransom amount. The malware continued to use an audio file to “speak” to its victims.
BleepingComputer now says that Cerber has switched to a four-character extension which is generated randomly. The name of the encrypted file is also scrambled, making it more difficult for users to recover their data. Additionally, the new malware variant drops a new ransom note, called README.hta.
The most important change in Cerber, however, is the threat’s ability to kill many database processes with the use of a close_process directive in the configuration file. These processes are terminated before the encryption process starts, so that the processes’ data files can be encrypted (the data file wouldn’t be accessible for encryption if the processes were still running).
The list of targeted processes includes: msftesql.exe, sqlagent.exe, sqlbrowser.exe, sqlservr.exe, sqlwriter.exe, oracle.exe, ocssd.exe, dbsnmp.exe, synctime.exe, mydesktopqos.exe, agntsvc.exeisqlplussvc.exe, xfssvccon.exe, mydesktopservice.exe, ocautoupds.exe, agntsvc.exeagntsvc.exe, agntsvc.exeencsvc.exe, firefoxconfig.exe, tbirdconfig.exe, ocomm.exe, mysqld.exe, mysqld-nt.exe, mysqld-opt.exe, dbeng50.exe, and sqbcoreservice.exe.
Just as the previous Cerber variants, the new ransomware iteration sends UDP packets to the 31.184.234.0/23 range for statistical purposes, researchers say.
Related: Cerber Ransomware-as-a-Service Generates $2.3 Million Annually: Report
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