Within 15 minutes, anyone with a decent amount of traffic to their own site can completely CORRUPT your Google Analytics data. It’s easy, simple, and once the data is corrupted, you can’t fix the data that’s already been collected.
How to Protect Yourself
All you need is a simple filter. It will only include traffic on your domain, protecting yourself from any data corruption when people hijack your Google Analytics Property ID.
To find your filters:
Go to your Google Analytics standard reports
Click on the “Admin” button in the top right
Click on “Filters”
Click “+ New Filter”
Then use these settings for your filter:
Select “Create New filter for Profile”
Name your filter with something snazzy like “Hacking Defense”
Select “Custom Filter”
For the Filter Field, select “Hostname”
If your site is LarsLofgren.com, you would define the filter pattern as “larslofgren\.com” and make sure to include a “\” before any “.”
Pick “No” for case-sensitive
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