502 Bad Gateway on logout after updating WordPress to 4.8.3

I have identified a glitch after updating my site to WordPress 4.8.3. If your site runs on Nginx (serving as a cache) coupled with Apache, every logout from WordPress will result in a 502 Bad Gateway error. The logout will complete, you can login back without issues, but the error on every logout looks really creepy.

If I deactivate your plugin, the issue is gone. When I re-enable your plugin, the issue is back. My Apache is 2.4, PHP 5.6.29 and with the latest stable build of Nginx.