As far as I can tell, there is no proper mitigation beyond patching. Unless we count turning off your service as a mitigation. Cloudflare is currently busy playing whack-a-mole with new vectors so it’s probably not feasible to properly mitigate it on the edge either.
Improper mitigation is still better than literally nothing - a simple "this may not cover everything, but block POST at the edge might help" can go a long way.
As far as I can tell, there is no proper mitigation beyond patching. Unless we count turning off your service as a mitigation. Cloudflare is currently busy playing whack-a-mole with new vectors so it’s probably not feasible to properly mitigate it on the edge either.
Improper mitigation is still better than literally nothing - a simple "this may not cover everything, but block POST at the edge might help" can go a long way.