Hi all,
Duo just released version 1.5.14 of Duo Network Gateway, which addresses the Let’s Encrypt “DST Root CA X3” root certificate, which expired today, September 30, 2021.
If you are running a version of Duo Network Gateway older than 1.5.14 and your upstream application or server has an expired Let’s Encrypt DST root in the full certificate chain, you may encounter a “502 Bad Gateway” error when trying to access a site behind Duo Network Gateway.
If that is the case, the remedy is to upgrade your Duo Network Gateway to version 1.5.14. For more information, refer to this Duo Knowledge Base article.
