Critical 'React2Shell' RCE Threatens Web Ecosystem as CISA Warns of Chinese 'BRICKSTORM' Malware Targeting Governments

This cybersecurity brief for December 4, 2025, covers a critical 10.0 CVSS RCE vulnerability, 'React2Shell' (CVE-2025-55182), affecting React and Next.js, now under active exploitation. Concurrently, a joint advisory from CISA, NSA, and Canada's Cyber Centre details the sophisticated 'BRICKSTORM' backdoor used by PRC state-sponsored actors against government and IT sectors. Other major developments include CISA adding actively exploited Android and SCADA vulnerabilities to its KEV catalog, a FinCEN report revealing over $2.1 billion in ransomware payments since 2022, and a significant data breach disclosure from Freedom Mobile.