learn.cisecutity.org is blocked

[yrro]

Similar to #405 (I can't re-open that issue), I'm seeing learn.cisecutity.org is blocked.

$ delv -i learn.cisecurity.org @8.8.8.8
; answer not validated
learn.cisecurity.org.	204	IN	CNAME	go.pardot.com.
go.pardot.com.		7178	IN	CNAME	pi.pardot.com.
pi.pardot.com.		271	IN	CNAME	pi-ue1.pardot.com.
pi-ue1.pardot.com.	9	IN	CNAME	pi-ue1-public-lb-f0209c6950285322.elb.us-east-1.amazonaws.com.
pi-ue1-public-lb-f0209c6950285322.elb.us-east-1.amazonaws.com. 26 IN A 3.92.120.28
pi-ue1-public-lb-f0209c6950285322.elb.us-east-1.amazonaws.com. 26 IN A 3.215.172.219
pi-ue1-public-lb-f0209c6950285322.elb.us-east-1.amazonaws.com. 26 IN A 18.208.125.13
pi-ue1-public-lb-f0209c6950285322.elb.us-east-1.amazonaws.com. 26 IN A 34.237.219.119
pi-ue1-public-lb-f0209c6950285322.elb.us-east-1.amazonaws.com. 26 IN A 52.54.96.194