Threadlinqs IntelligenceStart free

ATT&CK techniquePersistenceStealth (formerly Defense Evasion)

T1542 Pre-OS Boot

PersistenceStealth (formerly Defense Evasion)Enterprise

As of 2026-10-05, T1542 (Pre-OS Boot) appears in 23 tracked threats, first reported 2026-03-06 and most recently 2026-09-23, with linked actors including Chaotic Eclipse, INC Ransom, INC Ransom - G1032; it most often appears alongside T1068 (Exploitation for Privilege Escalation).

Tracked threats
2310 critical, 12 high, 1 medium
First seen
2026-03-06
Last seen
2026-09-23
Threat actors
7In the threats using it
Detection rules
16Blue tier and above

Data as of:

Activity timeline

T1542 first appeared in tracked threats on and was most recently reported on . The busiest month was 2026-07 with 7 reports, and 23 of the 23 threats were reported in the twelve months to 2026-09.

How adversaries use it

T1542 Pre-OS Boot is catalogued by MITRE ATT&CK under the Persistence and Stealth (formerly Defense Evasion) tactics in the Enterprise matrix. Threadlinqs maps 23 of 2623 tracked threats (0.9%) to it; by severity that is 10 critical, 12 high, 1 medium.

Threats that use T1542 most often also use T1068 Exploitation for Privilege Escalation (15 threats), T1082 System Information Discovery (14 threats), T1685 Disable or Modify Tools (14 threats), T1078 Valid Accounts (10 threats), T1190 Exploit Public-Facing Application (10 threats). These are the techniques an intrusion set tends to chain with it, so they are the natural next places to look when it is observed.

7 tracked threat actors appear in the threats that use T1542; the most frequent are Chaotic Eclipse (1), INC Ransom (1), INC Ransom - G1032 (1), Lynx (1), Nightmare Eclipse (1).

Mitigations

MITRE ATT&CK lists 5 mitigations for T1542.

Data sources

Telemetry that can reveal T1542, per MITRE ATT&CK.

  • Command — Command Execution
  • Drive — Drive Modification
  • Driver — Driver Metadata
  • File — File Creation, File Modification
  • Firmware — Firmware Modification
  • Network Traffic — Network Connection Creation
  • Process — OS API Execution

Threat actors using it

Tracked threats

23 tracked threats use T1542.

Detection coverage

Threadlinqs maintains 16 detection rules mapped to T1542 (SPL 6, KQL 5, Sigma 5). Rule content is available to Blue tier accounts and above; this page shows counts only.

16 detection rules (SPL/KQL/Sigma) · Blue and above. Compare plans

Sub-techniques

  • T1542.001 System Firmware — 8 tracked threats
  • T1542.002 Component Firmware — 1 tracked threat
  • T1542.003 Bootkit — 7 tracked threats
  • T1542.004 ROMMONkit — 0 tracked threats
  • T1542.005 TFTP Boot — 2 tracked threats