CVE-2026-98644

A flaw was found in the Linux kernel's Berkeley Packet Filter (BPF) subsystem. A local user could cause a Denial of Service (DoS) by executing batch lookup or deletion operations on large hash maps. Due to a missing rescheduling check when traversing consecutive empty hash table entries, the kernel can monopolize the processor for prolonged periods without yielding. This issue triggers a soft lockup condition, resulting in system unresponsiveness.

Red Hat rates this vulnerability as having a Moderate impact because triggering the denial of service requires high local privileges to create and interact with massive eBPF hash tables, limiting exposure to authorized administrative users. By default on Red Hat Enterprise Linux, unprivileged access to eBPF is restricted, which prevents regular users from initiating batch operations against kernel maps. Although an administrative caller can stall a CPU core by processing millions of empty hash buckets without voluntary rescheduling, the issue does not compromise system integrity or confidentiality.

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.