Agent AI—autonomous AI-powered attack tools—represent a critical emerging threat to Thailand's financial sector and SMEs. Attack success rates have jumped from 20% to over 90%, and time to compromise has collapsed from 4 months (2023) to 12-22 hours (2026). The financial sector is mobilizing through TB-CERT to coordinate cross-institutional cybersecurity response. Over 200 million Thai login credentials have already leaked to the dark web, making immediate adoption of AI-aware security protocols and sector-wide collaboration essential for business survival.