A critical remote code execution vulnerability (CVE-2025-3248) in Langflow has been actively exploited, allowing attackers to gain full control of vulnerable servers via an unprotected API endpoint. Organizations are urged to upgrade to version 1.3.0 or later to mitigate risks, as CISA warns of the high likelihood of exploitation and the potential existence of over 500 exposed instances. Those unable to upgrade should restrict access to Langflow services immediately.