Dark Herring malware was identified by a Zimperium research team, the campaign is estimated to be in the millions of dollars, in monthly increments of $15 per victim. Google has subsequently deleted all 470 fraudulent apps from Play Store, and the scam services have been shut down, however, any user who already has one of the apps loaded could be actively attacked in the future. The apps can also be found in third-party app shops.
Direct carrier billing (DCB) is a mobile payment technique which adds payments for non-telecom services to a consumer's monthly phone bill. It is used by customers worldwide, particularly in underbanked countries. It's a tempting target for opponents.
The Dark Herring's long-term success was based on AV anti-detection skills, widespread distribution via a large number of programs, code encryption, and the use of proxy as first-stage URLs.While none of the aforementioned features are novel or surprising, seeing it together in one software program is unusual for Android fraud. Furthermore, the actors used a complex infrastructure which has accepted communications from all 470 application users yet handled each one individually based on a unique identity.
It has no malicious code in the installed software, but it does have a hard-coded encoded string which refers to a first-stage URL located on Amazon's CloudFront.The server's answer includes links to further JavaScript files housed on Amazon Web Services servers, which are downloaded to the infected device.
The campaign was able to last so long because the malicious users presented viewers with the expected functionality, an attempt to remain installed on the victims' devices.
The Dark Herring applications begin interacting with the authoritarian (C&C) server once it has been installed on a device to send over the victim's IP address, which is used to track the victim for a direct carrier invoicing subscription.
The victim is sent to a geo-specific webpage, where the user is asked about personal details like phone numbers, ostensibly for verification purposes. However, the victim has no idea, of sending contact information to a subscription plan."The victim does not understand the impact of the crime right away," Zimperium explains, "and the chance of the theft extending for months before discovery is high, with hardly any remedy to get one's money back."
Given Dark Herring's evident accomplishments, Zimperium believes it is unlikely, the cybersecurity community will hear from this criminal outfit again.
