Bug with Finder after security update Safari 9.1.3

Hi,

I report a strange bug after I applied the security update "Safari 9.1.3".

All content displayed in Finder appeared like you can see in the screenshot. I tried to:

- relaunch Finder

- reset its preferences (ditching the .plist file(s))

- check the hardware (I recently added RAM, and tried removing banks one by one).

nothing worked

The only thing was restore a backup from Time Machine previous to the update. That solved the problem.

The question now is: do you think it is a random problem and I can try to reapply the update, or should I wait next version?

iMac 27" 2010, OS Maverick 10.9.5

Build 13F1911