# UMBRAL BISON

> As of 2026-08-03, UMBRAL BISON is a Belarus-nexus threat actor tracked by Threadlinqs Intelligence across 1 threat spanning vulnerability.

- **Nation:** Belarus
- **Tracked threats:** 1
- **Categories:** VULNERABILITY
- **As of:** 2026-08-03

## Tracked threats

- [CVE-2026-31431: Linux Local Privilege Escalation Actively Exploited by UMBRAL BISON Within 24 Hours of Disclosure](https://intel.threadlinqs.com/threat/TL-2026-1831) — HIGH

## Related CVEs

1 CVE referenced by tracked UMBRAL BISON activity.

- [CVE-2026-31431](https://intel.threadlinqs.com/cve/CVE-2026-31431)

## Full data

Infrastructure, IOC values and detection queries (Splunk SPL / Microsoft KQL / Sigma) require the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp

Canonical: https://intel.threadlinqs.com/actor/UMBRAL%20BISON