An overview of the activities of selected APT groups investigated and analyzed by ESET Research in Q2 2026 and Q3 2026

ESET researchers uncover MythicRatatoskr – a previously unknown Go-based backdoor hiding its C&C server inside the Yggdrasil mesh network – that paved the way for a destructive attack against a Ukrainian grain firm

ESET Research catalogs the changes of UAC-0099’s MATCHBOIL downloader from 2024 to 2026

ESET researchers document SparroWocky, the new flagship backdoor of the FamousSparrow APT group

ESET researchers discovered 11 vulnerable UEFI shim bootloaders signed by Microsoft that allow attackers to bypass UEFI Secure Boot by exploiting decade-old vulnerabilities

A view of the H1 2026 threat landscape as seen by ESET telemetry and from the perspective of ESET threat detection and research experts.