An issue was discovered in GitLab Community and Enterprise Edition before 11.1.7, 11.2.x before 11.2.4, and 11.3.x before 11.3.1. The diff formatter using rouge can block for a long time in Sidekiq jobs without any timeout.
https://about.gitlab.com/releases/2018/10/01/security-release-gitlab-11-dot-3-dot-1-released/