The home Trojan-banker known as Shylock has just been updated with new functions. According to the CSIS Security Group, during an investigation, researchers found that Shylock is now capable of spreading using the popular Voice over IP service and software application, Skype.
The program was discovered in 2011 that steals online banking credentials and other financial information from infected computers. Shylock, named after a character from Shakespeare’s “The Merchant of Venice”.
Shylock is active in only a few parts of the world. The epicenter of infections is primarily located in the UK.
The Skype replication is implemented with a plugin called “msg.gsm”. This plugin allows the code to spread through Skype and adds the following functionality:
– Sending messages and transferring files
– Clean messages and transfers from Skype history (using sql-lite access to Skype%smain.db )
– Bypass Skype warning/restriction for connecting to Skype (using “findwindow” and “postmessage”)
– Sends request to server: https://a[removed]s.su/tool/skype.php?action=…
Besides from utilizing Skype it will also spread through local shares and removable drives. Basically, the C&C functions allow the attacker to:
– Execute files
– Get cookies
– Inject HTTP into a website
– Setup VNC
– Spread through removable drives
– Update C&C server list
– Upload files
Shylock is one of the most advanced Trojan-banker currently being used in attacks against home banking systems. The code is constantly being updated and new features are added regularly.
As always for this type of Trojans antivirus detection is low.
The Trusteer research team recently uncovered a stealth new attack carried out by the SpyEye Trojan that circumvents mobile SMS (short message service) security measures implemented by many banks. Using code captured while protecting a Rapport user, researchers discovered a two-step web-based attack that allows fraudsters to change the mobile phone number in a victim’s online banking account and reroute SMS confirmation codes used to verify online transactions. This attack, when successful, enables the thieves to make transactions on the user’s account and confirm the transactions without the user’s knowledge.
In the first step of the attack, SpyEye steals the victim’s online banking login details. This is standard operating procedure for financial malware like SpyEye, Zeus, and others. The fraudsters can now access the victim’s account without raising any red flags that would be picked up by fraud detection systems.
In Step 2, SpyEye changes the victim’s phone number of record in the online banking application to one of several random attacker controlled numbers. In order to complete this operation the attacker needs the confirmation code which is sent by the bank to the customer’s original phone number. To steal this confirmation code the attacker uses the following social engineering scheme.
First, SpyEye injects a fraudulent page in the customer’s browser that appears to be from the online banking application. The fake page purports to introduce a new security system that is now “required” by the bank and for which customers must register. The page explains that under this new security process the customer will be assigned a unique telephone number and that they will receive a special SIM card via mail. Next, the user is instructed to enter the personal confirmation number they receive on their mobile telephone into the fake web page in order to complete the registration process for the new security system. This allows the criminals to steal the confirmation code they need to authorize changing the customer’s mobile number.
Now the fraudsters can receive all future SMS transaction verification codes for the hijacked account via their own telephone network. This allows them to use the SMS confirmation system to divert funds from the customer’s account without their knowledge, while not triggering any fraud detection alarms.