STRATQUAD
CYBER THREAT INTELLIGENCE BRIEF
Daily Brief · 21 June 2026 · 24h windowRISKLOW
StratQuad CTI Daily Brief, 21 June 2026
Compiled from 52 monitored sources · 1998 articles reviewed

Today’s Briefing

ESET published a detailed technical breakdown of The Gentlemen ransomware operation's GentleKiller suite, a centralised EDR-killer toolset that weaponises BYOVD exploits to disable endpoint security before encryption, corroborated by the group's own leaked internal data from May. Microsoft attributed the Mastra AI supply chain compromise.which poisoned more than 140 npm packages.to Sapphire Sleet, the North Korean group also tracked as BlueNoroff.

Top Stories

  1. Inside GentleKiller: The EDR-Killer Powering The Gentlemen
  2. Why Amazon hates 'human-in-the-loop' AI governance
  3. Microsoft links Mastra AI supply chain attack to North Korean hackers

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