Microsoft Warns ASCII Smuggling Is Being Used to Hide Phishing Keywords From Email Filters

Researchers observed a high-volume phishing campaign that inserted invisible Unicode tag characters into financial terms such as “funding,” “loan,” and “credit.” To recipients, the messages looked normal. However, the hidden characters split the words at the processing level, potentially preventing simple keyword-based filters from recognizing suspicious language. For example, the visible word “funding” could contain an invisible Unicode character between “fun” and “ding.” A…

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