Claude Mythos Fears Startle Japan's Financial Services Sector

Proofpoint published a set of Apr 2026 posts highlighting an uptick in AI-era and targeted threats across email, SaaS, collaboration apps and AI assistants. Research shows ~50% of organizations experienced AI-related incidents despite having AI security controls. Notable items include concerns about the ‘Claude Mythos’ model impacting Japan’s financial services, abuse of Microsoft 365 mailbox rules for data exfiltration and persistence, cargo/freight-focused threat actors running sophisticated remote access campaigns and using code-signing services to evade defenses, and exposure of FIFA World