Changes page shows changes formatted like:

3.51.0-develop-115 6e9834e8 (Dec 8, 2015 10:16:19 AM)   
(commit: 62369686076f3b2edc69c1497f31312dd173df5dtree) — unknown / githubweb

(screenshot attached)

Note the "tree" on the end of the commit sha1 above.

The commit URL is:
https://github.com/Company/app/commit/62369686076f3b2edc69c1497f31312dd173df5dtree

(private repo, sorry, using "Company" and "app" in place of actual names)

Removing the "tree" at the end goes to the correct page.

Jenkins job "github project is of the format:
https://github.com/Company/app
as is the repository URL