Visa issued a prenotice for a new JavaScript skimmer known as Baka, which will be flushed from memory after the stolen data is removed.
The credit card theft script was discovered by researchers with Visa's Payment Fraud Disruption (PFD) initiative in February 2020 while examining a command server and control (C2) which hosted a Skaming ImageID kit.
Last year, Visa discovered another skimmer JavaScript known as Pipka which quickly spread online stores after it was first spotted on a North American organization e-commerce site in September 2019.
Avoid detection and analysis
In addition to the standard basic scanning capabilities, such as configurable target form fields and data removal using image requests, Baka has an advanced design that shows that it is the project of a specialized malware programmer and comes with a unique blackout method.
Baka was spotted by Visa in several online stores in various countries and was observed during injection into infringing e-commerce stores from jquery-cycle [.] Com, b-metric [.] Com, apienclave [.] Com, quicdn [. ] com, apisquere [.] com, ordercheck [.] online and pridecdn [.] com domain.
The skimmer is added to the pages market of merchants, using a script tag and its loader uses to download the skimming code from the C2 server to run in memory.
This allows intruders to make sure that the password used to collect customer data will not be found when parsing files hosted on the merchant's server or client's computer.
Baka is also the first JavaScript malware (detected by Visa) and uses an XOR cipher to disguise the skimming code received from the C2 server.
Visa recommends that member financial institutions, e-commerce merchants, service providers, third party suppliers and resellers refer to the document What to do in a breach (WTDIC) for instructions if their payment systems are breached.
The company also shared the list of bestsellers practices for securing e-commerce platforms, as described by the PCI Security Standards Board.
