This signature detects an attempt to read the contents of the RAM of a system running a vulnerable version of OpenSSL, aka the Heartbleed attack. This signature detects a high rate of heartbeat requests from one client IP to one server IP (six in two seconds). This vulnerability is further documented as CVE-2014-0160.
Event action filters should be used to exclude IP addresses the signature alerts on that are not running vulnerable versions of OpenSSL.
A high rate of traffic from a NAT'ed client IP address could cause this signature to false positive.
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