Systems with microprocessors utilizing speculative execution and speculative execution of memory reads before the addresses of all prior memory writes are known may allow unauthorized disclosure of information to an attacker with local user access via a side-channel analysis, aka Speculative Store Bypass (SSB), Variant 4.

The SMTP binding function in Symantec Firewall/VPN Appliance 200/200R firmware after 1.5Z and before 1.68, Gateway Security 360/360R and 460/460R firmware before vuild 858, and Nexland Pro800turbo, when configured for load balancing between two WANs, might send SMTP traffic to a trusted network through an untrusted network.