For the second time since June 1, the handlers of CryptXXX ransomware have changed their ransom note and Tor payment site. More importantly to those developing detection signatures and administrators, this update no longer makes changes to the file extensions of encrypted files.
“To make it more difficult for administrators, this release no longer uses special extensions for encrypted files,” said researcher Lawrence Abrams on the BleepingComputer website. “Now an encrypted file will retain the same filename that it had before it was encrypted.”
Researcher and SANS Internet Storm Center handler Brad Duncan found the latest update to CryptXXX, in particular to post-infection activity. Duncan found the changes on a Windows machine compromised by the Neutrino Exploit Kit involved in the pseudo-Darkleech campaign.