Atlassian has told its users to patch its datacenter products, pronto, to prevent attackers accessing their files. The Australian collaborationware company on Monday sent users an email that opens with the words “Action required” and points to a security bulletin that explains CVE-2026-21589. The 9.3-rated arbitrary file access vulnerability is present in the datacenter versions of its Bitbucket, Confluence, Jira Service Management, Jira Software, Bamboo, Crowd, Crucible, and Fisheye products. Atlassian says the vulnerability “allows an unauthenticated attacker to access specific files within the web application root directory in affected versions.” That’s scary because Atlassian warns “In some configurations, there may be sensitive files present that increase your risk.” There’s also…