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New SesameOp Backdoor Malware Uses OpenAI API for C2

Cyber Security News by CyberSum.net
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Microsoft security researchers have discovered a new backdoor malware named SesameOp that uses the OpenAI Assistants API for covert command-and-control (C2) communications. The malware, found during a July 2025 cyberattack investigation, allows attackers to gain persistent access and remotely manage compromised devices. SesameOp leverages legitimate cloud services to avoid detection, encrypts harvested information, and establishes persistence through internal web shells. Microsoft advises security teams to audit firewall logs, enable tamper protection, and monitor unauthorized connections to mitigate the impact.

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By Cyber Security News by CyberSum.net