Massive Winos 4.0 Campaigns Target Taiwan


FortiGuard Labs recently observed several targeted phishing campaigns in Taiwan that use themes designed to exploit local business processes. These campaigns disseminate Winos 4.0 (ValleyRat) and subsequent malicious plugins through weaponized attachments or embedded links.

The lures mimic official communications, such as tax audit notifications, tax filing software installers, and cloud-based e-invoice downloads. Fortinet researchers analysis of domain registration data reveals that attackers use a rotating set of domains and cloud services to host and distribute malware. The highly volatile nature of this infrastructure renders traditional, static domain blocking insufficient as a primary defense. Over the past two months, the researchers have identified various delivery techniques, including malicious LNK files used for a downloader.

Read more…
Source: Fortinet


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