Patch ASAP: Max-Critical Atlassian Bug Allows Unauthenticated RCE

Executive summary: A max-critical unauthenticated remote code execution vulnerability (CVE-2023-22527, CVSSv3=10) affects multiple Atlassian Confluence Server and Data Center versions (notably 8.0.x–8.5.3 and some EOL releases). Atlassian released patches in its December update; there are no mitigations or workarounds, cloud instances are unaffected, and administrators are advised to immediately apply updates or remove affected instances from Internet exposure and monitor for malicious activity due to significant risk of exploitation for ransomware and espionage.