SB20261022213 - Inefficient Algorithmic Complexity in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Inefficient Algorithmic Complexity (CVE-ID: CVE-2026-98628)

CWE-ID: CWE-407 - Inefficient Algorithmic Complexity

CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a local privileged user to cause a denial of service through prolonged CPU consumption and delayed termination of a BPF loader task.

The vulnerability exists due to inefficient algorithmic complexity and missing signal checks and rescheduling points in the Linux kernel BPF post-verification instruction rewrite passes when processing specially crafted BPF programs. A local privileged user can submit a program containing 131072 unconditional jumps by zero followed by a valid return to trigger quadratic instruction removal in bpf_opt_remove_nops(), consuming CPU resources and preventing a pending SIGKILL from terminating the loader until rewriting finishes.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/261b61d3735b042ae25634f795c4540be0fc140c
• https://git.kernel.org/stable/c/56dc616d7a1f7d134d3e101c455e62b0a24d0cfd