ROP exploit prevented in Firefox/Chrome browser

Question

some users in my office are getting these alerts from sophos endpoint 
 "ROP exploit prevented in Firefox". 
 some user get it while using firefox, some in chrome. 
 is it due to thr website or is it due to the browser? 
 or is it a false alarm ?

Barb@Sophos · Answer

Hello yeowkm ,

Please have a look at this article
You can check your Event viewer for any 911 events to see if you can find more details regarding the detection.

As a next step, please follow this article.

Regards,

Steve Gutierrez · Answer

Hello, 
 
 I also have this same issue, see below for a workaround. 
 
 Current workaround is to either disable Branch Tracing in your threat protection policy, OR to opt out of site isolation in Chrome, which contains the features we're currently conflicting with. For instructions on how to opt out of site isolation in Chrome, please go to chrome://flags/#enable-site-per-process, and search for "Site isolation trial opt-out", and select "Opt-out" and save. 
 
 Best Regards, 
 Steve