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Showing posts with label Spam Bots. Show all posts

Users targeted with large number of Spam mails containing Banking Trojan

A new massive spam campaign has been spotted by security researchers at AppRiver which sends large amount of spam mails to data centers in an effort to evade Email-filtering engines.

AppRiver's data centers received 10 to 12 times normal traffic.  Even though AppRiver managed to block the spam mails, tremendous volume of traffic caused some of its customers delays in sending and receiving emails.

CyberCriminals are targeting users with large amount of emails with varying premise.  One of the spam mails is targeting Bank of America customers.  A fake alert message pretending to be from Bank of America contains a Bredo malware.

Researchers say the malware is capable of recording the keystrokes and steal financial information.  It has also capabilities to do download additional malware on the victim's machine.  The spam mails reportedly detected only by 11 out of 51 antiviruses.

Another mail analyzed by AppRiver is pretending to be from "VISA/MasterCard" and informs recipients that their account has been blocked due to unusual activity.

Some of the malicious attached files have pointed to Andromeda botnet and some other pointing to Bredo Botnet.  This botnet activity being referred as TidalWave/TidalBotnet by AppRiver.

Dutch Authorities take down C&C servers used by Grum Botnet

Dutch Authorities did a great job by taking down two of the command and control(C&C) servers belong to  the world's largest spam botnet ,Grum. This is not complete victory, as there are still two other C&C servers at work, but researchers are optimistic that the volume of spam will drop as a result.

Last week, FireEye published the details on four C&C servers, actively controlling the Grum botnet.Two of the servers were in the Netherlands, one is in Russia and the other in Panama.

Now, Dutch authorities take down the two Secondary C&C servers located in the Netherlands.  The master CnC servers located in Panama and Russia are still alive.

"These two CnC servers were responsible for pumping spam instructions to their zombies. With these two servers offline, the spam template inside Grum's memory will soon time out and the zombies will try to fetch new instructions but will not able to find them," FireEye’s Atif Mushtaq wrote.

“Ideally this should stop these bots from sending more spam. I am sure the absence of the spam sent by the world's third largest spam botnet will have a significant impact on the global volume.”