Performance Metrics Collector Daemon (PMCD) in Performance Copilot in IRIX 6.x allows remote attackers to cause a denial of service (resource exhaustion) via an extremely long string to the PMCD port.
https://exchange.xforce.ibmcloud.com/vulnerabilities/4284
http://archives.neohapsis.com/archives/bugtraq/2000-04/0056.html