Ruby Sleet
Aliases: CERIUM, VELVET CHOLLIMA
- First seen
- 2019-01-01 00:00:00
- Origin
- KP
- Primary motivation
- espionage
- Sophistication
- advanced
- Resource level
- government
- Actor type
- nation-state
- Last IoC activity
- 2026-07-20 19:40:50
- Profile updated
- 2026-07-07 12:12:54
Targeted industries: government-and-public-sector healthcare-and-pharmaceutical technology-and-telecommunications
Targeted regions: country_code:us country_code:gb country_code:kr country_code:de
Context
Ruby Sleet is a threat actor linked to North Korea's Ministry of State Security. Cerium has been involved in spear-phishing campaigns, compromising devices, and conducting cyberattacks alongside other North Korean threat actors. They have also targeted companies involved in COVID-19 research and vaccine development.
Related threat objects
- Kimsuky (threat-actor)
Reports & references
- Microsoft — Health Care Cyberattacks Covid 19 Paris Peace Forum (report)
- raw.githubusercontent.com — Microsoftmapping (report)
- Microsoft — Microsoft Threat Actor Naming (report)