One Packet Can Crash OT Servers in Industrial Sectors

TDengine contains a high-severity integer-underflow vulnerability (CVE-2026-42542, CVSS 7.5) in pre-auth message parsing that allows an unauthenticated attacker to crash servers by sending a single malformed packet to TCP port 6030; TDengine released version 3.4.1.6 to fix the issue and Ridge Security developed a private proof-of-concept but has seen no in-the-wild exploitation. Organizations—especially in industrial, IoT, energy, and automotive sectors—are urged to apply the patch or restrict access to port 6030 to avoid operational-impacting denial-of-service.