When using proxy or SSL inspection devices, it's vry nice to be able to test for various ssl errors. The site and when use with your client-browser can assist and help with identifying errors.
Each browser can exhibit differences in alert or warnings or errors based on; browser type, revision, security settings, any path or MiTM inspection devices, etc.....
badssl dot com has had this site out for a while & with the means to draft various browser conditions and by clicking that link you can create that condition
examples of just some of the conditions
So let's say you want to check your browser error and function with a expired_certificate & the reported outcome.
( examples )
I've used this site when testing the FortiGate ssh inspection or other security appliance that handles HTTPs inspections or MiTM. Or to find out if your HTTPS proxy does any certificate validations.
kfelix @ socpuppets.com
NSE ( network security expert) and Route/Switching Engineer
kfelix -----a----t---- socpuppets ---dot---com
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