Some customers who use AWS WAF with Application Load Balancer (ALB) or API Gateway in the AP-NORTHEAST-1 Region are experiencing slow propagation of AWS WAF rule changes and an increase in blocked web requests. We have identified the root cause and are working to fix the issue. Until the issue is resolved, customers using AWS WAF with Application Load Balancer can optionally configure ALB to forward requests to targets by enabling the WAF fail open attribute (https://docs.aws.amazon.com/elasticloadbalancing/latest/application/application-load-balancers.html#load-balancer-waf), and customers using AWS WAF with API Gateway can temporarily disable affected Web ACLs.