Remote Overlay Toolkit Makes Online Banking Fraud Easy

A new toolkit discovered late last year by researchers at IBM Trusteer allows even less skilled cybercriminals to steal online banking credentials and abuse them for fraudulent transactions.

The toolkit, dubbed KL-Remote, is used for remote overlay attacks which enable cybercrooks to access online banking accounts directly from victims’ computers without raising too much suspicion.

The threat has been spotted in Brazil, a country where, according to studies, criminals made $264 million in 2013 through Internet banking fraud. KL-Remote is interesting because, unlike many other pieces of financial malware, it requires manual intervention from the individual who controls it.

According to researchers, an attack involving KL-Remote starts with the attacker installing the toolkit on the target’s computer, usually with the aid of other malware. Once installed, the threat monitors victims’ online activities to see if they access the websites of certain financial institutions.

When one of the targeted sites is accessed, the individual who controls the malware is alerted and provided with information on the victim’s device, including IP address, operating system, processor, and connection speed.

The toolkit comes with an easy-to-use graphical interface that shows the victim’s desktop and what they’re typing. The interface also includes features for taking control of the mouse and the keyboard, and for presenting victims with various messages that can be used to obtain valuable information.

The threat takes a screenshot of the banking website and displays it to the user. The cybercriminal then uses the tool to push a message on top of that image. The message is different for each website and it instructs victims to enter the information needed by the attacker to gain access to the banking account. This information can include usernames and passwords, and one-time passwords generated by security devices provided by banks to their customers.

Once the information is handed over by the victim, KL-Remote displays a new message instructing them to wait until the process is completed. While the user waits, the attacker takes control of the computer and logs in to the online banking account. The fraudster’s actions are not seen by the victim because everything takes place behind the screenshot displayed on the screen.

IBM Trusteer researchers highlight that such a tool can be highly effective in bypassing traditional anti-fraud mechanisms. That’s because the attacker can obtain the information needed to access the account simply by requesting it from the victim, and since every action is performed directly from the user’s computer, which is considered a trusted devices, no red flags are raised.

According to experts, remote overlay attacks can be mitigated on the client side by ensuring that the endpoint doesn’t become infected with malware in the first place. On the server side, such attacks can be detected by looking for evidence of a malware infection, unusual browsing patterns, the use of remote access tools to log in to the banking account, and unusual transactions.

“Toolkits such as KL-Remote — which package a preconfigured fraud flow in a user-friendly GUI — greatly expand the pool of people who can commit banking fraud. With the toolkit, a criminal with basic technical skills can perform high-end fraud attacks that can circumvent strong authentication. Furthermore, the ability to embed the toolkit in types of common malware greatly increases its availability and reach,” Ori Bach, senior product marketing manager at Trusteer, wrote in a blog post.

KL-Remote is currently only available in Brazil with the phishing messages written in Portuguese, but researchers have determined that the toolkit can be adapted for other countries as well. The fraud toolkit costs less than $400, IBM Tursteer told SecurityWeek.

On Tuesday, IBM unveiled the z13, a sophisticated mainframe computer that provides real-time encryption and analytics for securing mobile transactions and preventing fraud.

*Updated with KL-Remote pricing information