A critical denial of service vulnerability in the Ceph RGW daemon, identified as CVE-2024-47866, allows unauthenticated remote attackers to crash storage services.

The vulnerability stems from improper input validation within the RGW daemon, where processing an empty string in the x-amz-copy-source HTTP header leads to an unhandled exception. This attack vector is accessible to unauthenticated remote users, requiring no specific privileges to trigger the crash.

The ability for an unauthenticated attacker to remotely crash the RGW daemon poses a significant threat to data availability in environments relying on Ceph for object storage. With a CVSS score of 7.5, the impact is high because it allows for the total disruption of storage services, potentially halting business operations that depend on these storage backends.

Immediate Action: As no patched version is currently available, administrators should restrict access to the RGW interface by implementing network-level access controls or firewall rules to limit exposure to trusted networks.

Proactive Monitoring: Monitor RGW daemon logs for frequent service restarts or error messages related to object copy operations, which may indicate active exploitation attempts.

Compensating Controls: Deploy a Web Application Firewall (WAF) or an API gateway configured to inspect and block HTTP requests containing malformed or empty x-amz-copy-source header values.

Public Exploit Available: No (exploit_available: false)

Given the lack of an official patch at this time, organizations must prioritize compensating controls to shield the RGW daemon from unauthorized access. Monitor the official Ceph security advisories closely for the release of a fix and be prepared to deploy the update immediately upon availability to restore service resiliency.