Visa issued one warning for a new JavaScript skimmer known as Baka, which will be deleted from the μνήμη 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 and control (C2) server hosting an ImageID skaming kit.
Last year, Visa discovered another skimmer JavaScript known as Pipka which quickly spread to online stores after it was first spotted on an e-commerce site of North American organizations in September 2019.
Avoid detection and analysis
Apart from the regular basics possibilities scanning features such as configurable target form fields and data extraction using image requests, Baka also features an advanced design that suggests it is a project of a specialized malware developer and comes with a unique obfuscation 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 merchants' purchase pages, using a script tag, and the loader uses it to download the skimming code from the C2 server to run it in memory.
This allows attackers to ensure that the code used to collect customer data will not be found when analyzing files hosted on the merchant's server or computer the customer's.
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.
Η company also shared the best list practices for securing e-commerce platforms, as described by the PCI Security Standards Board.