MerkSpy: Exploiting CVE-2021-40444 to Infiltrate Systems


Spyware is malicious software engineered to covertly monitor and gather information from a user’s computer without their awareness or consent.

It can record activities like keystrokes, browsing behavior, and personal information, often transmitting this data to a third party for espionage or theft. FortiGuard Labs recently detected an attack exploiting the CVE-2021-40444 vulnerability in Microsoft Office. This flaw allows attackers to execute malicious code via specially crafted documents. In this instance, the exploitation led to the deployment of a spyware payload known as “MerkSpy.” MerkSpy is designed to clandestinely monitor user activities, capture sensitive information, and establish persistence on compromised systems.

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Source: Fortinet


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