Modular Java Backdoor Dropped in Cleo Exploitation Campaign


While investigating incidents related to Cleo software exploitation, Rapid7 Labs and MDR observed a novel, multi-stage attack that deploys an encoded Java Archive (JAR) payload. Our investigation revealed that the JAR file was part of a modular, Java-based Remote Access Trojan (RAT) system.

This RAT facilitated system reconnaissance, file exfiltration, command execution, and encrypted communication with the attacker’s command-and-control (C2) server. Its modular architecture includes components for dynamic decryption, network management, and staged data transfer.

Read more…
Source: Rapid7


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