The TCP/IP networking module in Unisys ClearPath MCP systems with TCP-IP-SW 57.1 before 57.152, 58.1 before 58.142, or 59.1 before 59.172, when running a TLS 1.2 service, allows remote attackers to cause a denial of service (network connectivity disruption) via a client hello with a signature_algorithms extension above those defined in RFC 5246, which triggers a full memory dump.