of MongoDB , ElasticSearch , Hadoop , CouchDB , and Cassandra servers , attackers are now hijacking hundreds of MySQL databases , deleting their content , and leaving a ransom note behind asking forAttack.Ransoma 0.2 Bitcoin ( $ 235 ) paymentAttack.Ransom. According to breach detection firm GuardiCore , the attacks are happening via brute-force attacks on Internet-exposed MySQL servers , and there 's plenty of those laying around since MySQL is one of today 's most popular database systems . All attacks came from a server in the Netherlands Based on currently available evidence , the attacks started on February 12 , and only lasted for 30 hours , during which time attackers attempted to brute-force their way into MySQL root accounts . Investigators said all attacks came from the same IP address from the Netherlands , 109.236.88.20 , belonging to a hosting company called WorldStream . During their ransackingAttack.Databreach, attackers did n't behave in a constant pattern , making it hard to attribute the hacks to one group , despite the usage of the same IP . For example , after gaining access to MySQL servers , attackers created a new database called PLEASE_READ and left a table inside it called WARNING that contained their ransom demandsAttack.Ransom. In some cases , attackers only created the WARNING table and left it inside an already existing database , without creating a new one . Investigators report that attackers would then dump the database 's content and delete it afterward , leaving only the one holding their ransomAttack.Ransom. In some cases , attackers deleted the databases without dumping any data . Attackers have their own website Two ransom notes have been found in the hundreds of confirmed attacksAttack.Ransom, one askingAttack.Ransomvictims to get in contact via email and confirm the payment , while the other used a completely different mode of operation , redirecting users to a Tor-hosted website . The two Bitcoin addresses listed in the ransom notes received four and six paymentsAttack.Ransom, respectively , albeit GuardiCore experts doubt that all are from victims . `` We can not tell whether it was the attackers who made the transactions to make their victims feel more confident about payingAttack.Ransom, '' they said . Be sure the attacker still has your data Just like in the case of the now infamous MongoDB attacksAttack.Ransomthat have hitAttack.Ransomover 41,000 servers , it 's recommended that victims check logs before deciding to payAttack.Ransomand see if the attackers actually took their data . If companies elect to pay the ransomAttack.Ransom, should always ask the attacker for proof they still have their data . None of this would be an issue if IT teams follow standard security practices that involve using an automated server backup system and deleting the MySQL root account or at least using a strong and hard-to-brute-force password . This is not the first time MySQL servers have been held for ransomAttack.Ransom. The same thing happened in 2015 , in a series of attacksAttack.Ransomcalled RansomWebAttack.Ransom, where attackers used unpatched phpBB forums to hijack databases and hold websites up for ransomAttack.Ransom.