UNC5266

Primary motivation
espionage
Sophistication
advanced
Resource level
government
Actor type
nation-state
Profile updated
2026-07-07 12:11:52

Targeted industries: government-and-public-sector technology-and-telecommunications

Context

Mandiant created UNC5266 to track post-disclosure exploitation leading to deployment of Bishop Fox's SLIVER implant framework, a WARPWIRE variant, and a new malware family that Mandiant has named TERRIBLETEA. At this time, based on observed infrastructure usage similarities, Mandiant suspects with moderate confidence that UNC5266 overlaps in part with UNC3569, a China-nexus espionage actor that has been observed exploiting vulnerabilities in Aspera Faspex, Microsoft Exchange, and Oracle Web Applications Desktop Integrator, among others, to gain initial access to target environments.

Reports & references

  • cloud.google.com — Ivanti Post Exploitation Lateral Movement (report)

External references