CVE-2026-89799

A flaw was found in the Linux kernel's Berkeley Packet Filter (BPF) component. Specifically, within the bpf_get_stackid function, preemption was not properly disabled when calling get_perf_callchain and accessing its trace entries buffer. This oversight could lead to a race condition, where multiple operations might interfere with each other. Such an issue could result in system instability, unintended information disclosure, or a denial of service (DoS) to the affected system.

This flaw is rated with a Moderate severity for Red Hat Enterprise Linux because exploitation requires local system privileges capable of loading tracing BPF programs, which substantially limits the attack surface in standard enterprise environments. Under default configurations, loading programs that invoke callchain stack retrieval helpers requires elevated capabilities such as CAP_BPF or CAP_SYS_ADMIN. Consequently, an unprivileged local user cannot directly trigger this race condition, restricting the potential threat of kernel memory corruption or denial of service to already privileged workloads.

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.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.