CVE-2026-89647

A flaw was found in the Linux kernel's Ceph file system. The ceph_trim_dentries() function, when invoked by ceph_cap_reclaim_work(), can enter an infinite loop under specific conditions where no leases need to be reclaimed. This busy loop causes excessive CPU utilization, potentially leading to a Denial of Service (DoS) for affected systems.

This vulnerability is rated as Low severity because exploitation requires an active CephFS client mount and does not compromise system integrity or expose sensitive data. In typical Red Hat Enterprise Linux environments, the Ceph kernel driver is not loaded or configured by default. Impact is limited to elevated CPU consumption and lock contention during background directory lease scanning when no entries qualify for reclamation, avoiding kernel crashes.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.