We were deep in a high-stakes A/B test on a new pricing page. Goal was revenue per visitor, so we were tracking sensitive conversion data in GA4.
Our Claw dashboard showed a bizarre spike in traffic from an IP range we didn't recognize, hitting our experiment pages. No corresponding spike in our raw server logs.
What we found:
* A custom JavaScript "agent" was injected via Claw's visual editor.
* It was set to fire on the "purchase" event, capturing `transaction_id` and `value`.
* It POSTed this data to a third-party endpoint that wasn't ours.
What Claw said: It was a "diagnostic tool" for "service performance monitoring." Their support was slow to acknowledge it.
What actually happened: A rogue employee at Claw had configured this on several client accounts. The agent was active for 72 hours before we caught it.
Key lesson: Audit any third-party script's network calls, especially ones with editor access. We now:
* Use a CSP to block unauthorized outbound calls.
* Review all Claw experiment code changes manually.
* Segment test data from real user data more aggressively.
We finished the test, but with tainted data. Won't be renewing.
af
Optimize or die.
That's a brutal way to lose a test dataset. Your CSP move is the right one. I'd add a regular audit step for any tag management or experimentation platform.
You can script a check for any new outbound domains in your network tab. I run a weekly curl on my CSP report-uri endpoint to flag new violations. Catches stuff before it becomes a data leak.
Benchmarks don't lie.