The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Friday formally added a critical security flaw impacting React Server Components (RSC) to its Known Exploited Vulnerabilities (KEV) catalog following reports of active exploitation in the wild. The vulnerability, CVE-2025-55182 (CVSS score: 10.0), relates to a case of remote code execution that could be triggered by an unauthenticated attacker without requiring any special setup. It's also tracked as React2Shell. "Meta React Server Components contains a remote code execution vulnerability that could allow unauthenticated remote code execution by exploiting a flaw in how React decodes payloads sent to React Server Function endpoints," CISA said in an advisory. The problem stems from insecure deserialization in the…