In a recent incident response (IR) case, Kaspersky researchers discovered highly customized malware targeting Exchange infrastructure within government environments.
Analysis of detection logs and clues within the sample suggests that the Exchange server was likely compromised via a known N-day vulnerability. Kaspersky in-depth analysis of the malware revealed a sophisticated, multi-functional backdoor that can be dynamically extended with arbitrary functionality through the download of additional modules. Notably, the attackers leveraged several open-source projects to build this backdoor. Once loaded, the backdoor grants the attackers full control over the Exchange server, allowing them to execute a range of malicious activities.
Read more…
Source: Kaspersky
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