Process and analysis
What is Patch?
A vendor fix for a known flaw, and the act of applying it.
A patch is a vendor update that fixes a known flaw, and patching is the act of applying it. Patches range from routine monthly updates to emergency fixes for vulnerabilities already being exploited.
The gap between a patch being released and being applied is where much exploitation happens. Attackers compare patched and unpatched versions to work out the flaw, so publishing a fix can speed up attacks against anyone who waits.