After the Imunify360 update, the warning is received in the Imunify360 dashboard:
Hyperscan technology provides greatly improved malware scanning speed on CPU with SSE3 instructions support. Requires extra 50MB of RAM to operate.
What should be done about it?
It is an optional feature and just affects the scan performance. When enabled, it uses the high-performance hyperscan library.
If the servers' CPU is already prepared for it, the feature can be enabled to improve scanning performance in Imunify360 > Settings > Malware:
Note that the "medium" status of warning does not require immediate action and serves only to inform about the feature that can be considered for enabling.
How do I check if my CPU supports this?
The Hyperscan feature requires a CPU that supports the SSSE3 CPU instruction set. It's is a high-performance software library that takes advantage of recent CPU architecture advances. At a minimum, support for Supplemental Streaming SIMD Extensions 3 (SSSE3) is required, which should be available on any modern x86_64 processor.
You can check if your processor supports SSSE3 on your guest by:
cat /proc/cpuinfo | grep -E "^(flags|model nam)"
It will expose all flags available.
If It does not have SSSE3 support, you may need to make sure that that flag is passed thru the hypervisor, if you are inside a guest-VM mean, the -cpu flag, taking Linux QEMU/KVM Hypervisor as example:
To pass all available host processor features to the guest:
# qemu -cpu host ...
or just appending ssse3 instructions:
# qemu -cpu qemu64,+ssse3 ...
However, the underlying processor from the host/hypervisor should have support to it, whereas if it's a bare metal server you may check the CPU the same way. Find a list of CPUs with that capability here: https://en.wikipedia.org/wiki/SSSE3