A flaw in the Linux kernel's libceph module allowed an attacker to supply a malicious incremental osdmap epoch that would trigger a BUG_ON, causing an unexpected kernel panic. The issue was addressed by changing the code to detect the invalid epoch and simply mark the osdmap as invalid instead of crashing, thereby removing the denial‑of‑service vector. The weakness is a logic error that was previously triggered by unsanitized input, identified as CWE‑617. The primary impact is a loss of availability for the affected host, with no known confidentiality or integrity compromise.

The vulnerability applies to all Linux kernel releases prior to the patch that introduced the change in osdmap_apply_incremental(). The CPE list includes many kernel versions, but the exact impacted releases are not specified. Users of any Linux distribution that contains an unpatched kernel containing the libceph module are potentially affected.

The CVSS score of 5.5 indicates moderate severity. The EPSS score of less than 1% signifies a very low likelihood of exploitation in the wild, and the vulnerability is not listed in the CISA KEV catalog. Attackers would need to supply a malformed Ceph osdmap to the kernel, which can be done via Ceph client or control plane interactions; therefore the attack vector is likely local or remote through malicious Ceph traffic. The patched version eliminates the crash, so the remaining risk is limited to availability degradation on systems that cannot be updated quickly.