Less than a month after Security Intelligence announced the discovery of the brand-new and highly advanced banking Trojan Shifu, our predictions materialized and the malware has spread from Japan and begun actively attacking U.K. banks and wealth management firms.
Shifu, which is suspected to have been created by Russian-speaking malware authors, only targeted 14 Japanese banks at the time of its discovery and also focused on a select set of electronic banking platforms used across Europe. However, due to the threat’s level of sophistication, IBM Security X-Force researchers predicted it would spread into new territories in the near future. As of Sept. 22, that prediction is a reality, with the U.K. receiving its very own Shifu configuration with 18 new targets.
Shifu Moves to the UK
X-Force researchers confirmed that Shifu is actively attacking online banking customers in order to perform fraudulent transactions.
The Shifu Trojan may be new crimeware, but its inner workings are not entirely unfamiliar. The malware relies on a few tried-and-true Trojan mechanisms from other infamous crimeware codes. It appears that Shifu’s internal makeup is being composed by savvy developers who are intimately familiar with other types of banking malware.
Beyond dressing Shifu with select features from the more nefarious codes known to information security professionals, these developers are already working on internal changes to Shifu. These are designed to ensure the Trojan’s security evasion mechanisms continue to perform.
For example, in its new, U.K.-dedicated samples, Shifu no longer injects into the explorer.exe process. Rather, it has modified its action path to launch a new svchost instance and performs all actions from that process instead.
Infection Campaign Status
Shifu began spreading to U.K.-based endpoints in mid-September 2015, with a few machine infections per day. By Sept. 22, it became clear that an actual infection campaign was taking place and hundreds of endpoints were infected per day.
Although one relatively modest campaign has already taken place, IBM X-Force researchers believe more widespread infection sprees are yet to come in the U.K. This is likely to be followed with future propagation into other parts of Europe and the U.S.
To infect users, online banking and wealth management customers are being led to poisoned websites hosting the Angler exploit kit (EK), likely through links in email spam.
Although Angler is used by many cybercriminals, they all rely on its ability to evade security mechanisms and its multistep attack technique. To keep automated security off its tracks, Angler attacks are based on a redirection scheme that begins with a clean page or advertising banner and eventually lands on an Angler-poisoned page. The victim’s endpoint is then scanned for the corresponding vulnerabilities, followed by exploitation and the eventual payload drop.
As more information about the evolution of the Shifu Trojan develops, be sure to check back for updated findings and reports.