We just received word of an exploit from Atlassian (makers of Confluence) that affects the versions of Confluence we host on-site. They do not yet have a fix. Until they do, access to collab.cels.anl.gov, confluence.cels.anl.gov, and wiki.jlse.anl.gov will be limited to internal access only. (We are separately dealing with an issue with wiki.jlse.anl.gov such that it may not be online until tomorrow.)
Update 10AM June 3: Proper security mitigations are in place with our Web Application Firewall (WAF) via Cloudflare that we are able to turn on external access again. This will take some time to work through various DNS caches.