Microsoft Flash embedded in Internet Explorer
Microsoft Flash was end-of-support at the end of December 2020 and is now unsupported and whilst an extremely useful application / plug-in over the years, it is also one of the top compromised applications that we have seen over the years.
Flash Player has over 1100 recognised vulnerabilities, including critical bugs and now the product is no longer supported any new identified issues will remain indefinately unpatched.
Microsoft have a KB to address the Adobe Flash issue or more accurately remove Flash from your system and you can find the required update for your system here