nss-3.16.1-7.el6_5.x86_64 came in via automatic updates overnight.<br />
<br />
The next day, none of my WooCommerce orders made via PayPal were going through.<br />
<br />
I investigated, using the WooCommerce PayPal IPN logs, and the cause was that when WooCommerce tried to connect to www.paypal.com via https, the SSL certificate validation was failing. This was repeatable - every time, every order.<br />
<br />
I asked myself "what's changed", looked at the yum logs, and saw that only one set of RPMs had been updated in the last overnight automatic updates - nss. I rolled this back, re-ran the IPN events, and everything worked (again, every time).
↧
