New YiBackdoor Malware Shares Major Code Overlaps with IcedID and Latrodectus

Cybersecurity researchers have disclosed details of a new malware family dubbed YiBackdoor that has been found to share "significant" source code overlaps with IcedID and Latrodectus .

"The exact connection to YiBackdoor is not yet clear, but it may be used in conjunction with Latrodectus and IcedID during attacks," Zscaler ThreatLabz said in a Tuesday report. "YiBackdoor is able to execute arbitrary commands, collect system information, capture screenshots, and deploy plugins that dynamically expand the malware's functionality."

The cybersecurity company said it first identified the malware in June 2025, adding it may be serving as a precursor to follow-on exploitation, such as facilitating initial access for ransomware attacks. Only limited deployments of YiBackdoor have been d