Malicious Android apps targeting Malaysian bank customers

Researchers at cyber security firm ESET have analysed three malicious Android applications targeting customers of eight Malaysian banks.

To make a profit off customers who have increasingly turned to online shopping during the pandemic, cybercriminals are tricking these eager shoppers into downloading malicious applications, the company says.

In an ongoing campaign, the threat actors are trying to steal banking credentials by using fake websites that pose as legitimate services, sometimes outright copying the original. These websites use similar domain names to the services they are impersonating.

"To make the already couch-friendly approach of online shopping even more convenient, people are increasingly using their smartphones to shop," says  says ESET researcher Luk tefanko, who analysed the malicious applications.

"Smartphone purchases make up the majority of online shopping orders most of them from vendor-specific applications," he says.

This campaign was first reported at the end of 2021, with the attackers impersonating the legitimate cleaning service Maid4u. Distributed through Facebook ads, the campaign tempted potential victims to download Android malware from a malicious website. In January 2022, MalwareHunterTeam identified three more malicious websites and Android trojans attributed to this campaign. Recently, ESET researchers found four additional fake websites. All seven websites impersonated services that are only available in Malaysia.

The copycat websites do not provide an option to shop directly through them. Instead, they include buttons that claim to download apps from Google Play.

However, clicking these buttons does not actually lead to the Google Play store, but to servers under the threat actors control. To succeed, this attack requires the intended victims to enable the non-default Install unknown apps option on their devices.

When the time comes to pay for the order, the victims are presented with payment options they can pay either by credit card or by transferring the required amount from their bank accounts.

At the time this research was active, it was not possible to select the credit card payment option.

After picking the direct transfer option, victims are presented a fake FPX payment page and asked to choose their bank out of the eight Malaysian banks provided, and then enter their credentials. After the victims submit their banking credentials, they receive an error message informing them that the user ID or password they provided was invalid.

At this point, the entered credentials have been sent to the malware operators. To make sure the threat actors can get into their victims bank accounts, the fake e-shop applications also forward all SMS messages received by the victim to the operators in case they contain Two-Factor Authentication (2FA) codes sent by the bank.

"While the campaign targets Malaysia exclusively for now, it might expand to other countries and banks later on," says tefanko.

" At this time, the attackers are after banking credentials, but they may also enable the theft of credit card information in the future," he says.

"ESET Research has found the same malicious code in all three analysed applications, leading us to conclude that they can all be attributed to the same threat actor."

To protect yourself against this type of threat, first, try to ensure that you are using legitimate websites to shop:

• Verify if the website is secure, i.e., its URL begins with https://. Some browsers might even refuse to open non-HTTPS websites and explicitly warn users or provide an option to enable HTTPS-only mode.
• Be wary of clicking on ads and paid search engine results
• Pay attention to the source of applications you are downloading. Make sure that you are actually redirected to the Google Play store.
• Use software or hardware 2FA instead of SMS when possible and use mobile security solutions.