Adobe Flash is problematic software. It is software that tends to linger on computers unpatched and full of vulnerabilities, and so has become a common vector for malware and ransomware infections. A 4th zero day exploint in 4 months has been announced, which means more ways your computer can become compromised. In addition to the security problems, it is also a resource hog. This is the main reason Flash has never been allowed to run on Apple iOS devices.
So seriously, uninstall flash where possible. If you absolutely do need it, make sure it is set to install patches automatically.