A quarter of a million databases stolen from tens of thousands of breached MySQL servers are being offered for sale on the dark web, according to security researchers from Guardicore Labs.
Hackers are believed to have obtained 7TB of stolen data using the PLEASE_READ_ME ransomware campaign, successfully targeting around 83,000 MySQL database servers.
PLEASE_READ_ME has reportedly been active since January 2020, attacking weak credentials on internet-facing MySQL servers.
Since then, Guardicore Global Sensors Network (GGSN) reported 92 attacks, with numbers rising sharply in October. According to Guardicore researchers, the ransomware attacks originated from 11 different IP addresses, most of which were found to be located in the UK and Ireland.
The ransomware campaign is untargeted, meaning that it attempts to infect any of the five million MySQL servers which are internet-facing. Hackers exploit weak credentials and are able to re-access the network by leaving a backdoor user on the database for persistence.
Guardicore Labs researchers managed to discover two different variants during the lifetime of this campaign. The first, which lasted from January to the end of November, saw attackers leaving their victims a ransom note with their wallet address, the amount of Bitcoin to pay, as well as an email address for technical support, with 10 days being given to make the payment.
The second variant, which began on 3 October and also lasted until late November, got rid of the Bitcoin wallet payments and email communications. Instead, hackers opted for a website in the Tor network to receive payments and used unique alphanumeric tokens, outlined in the ransom notes, to identify the victims.
In a blog post detailing the discovery, security researchers Ophir Harpaz and Omri Marom said that the “PLEASE_READ_ME operators are trying to up their game by using double extortion in scale”.
“Factoring their operation will render the campaign more scalable and profitable. Guardicore Labs provides an IOCs repository and will keep monitoring this campaign to help organizations protect against it,” they added.
