Another great example is how Claude is helping Mozilla find zero day exploits in Firefox, by the hundreds, and ranging from minor to CVE level, for over a year:
https://blog.mozilla.org/en/firefox/hardening-firefox-anthro...
I think the Mozilla example is a good one because its a large codebase, lots of people keep asking "how does it do with a large codebase" well there you go.
And you can check the list of bugs being discovered by Anthropic's Red Team: https://red.anthropic.com/