SB20260812184 - NULL pointer dereference in Linux kernel sched

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-68337)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a NULL pointer dereference in the bpf_redirect helpers and skb_do_redirect() when processing tc BPF programs attached to a proper qdisc without a bpf_net_context. A local user can attach or run a BPF program that calls a redirect helper or returns TC_ACT_REDIRECT to cause a denial of service.

The issue occurs on qdisc paths where tc BPF execution does not establish the required per-task network context.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/3f4920d165b29052255527d8ae7619e7ec132ece
• https://git.kernel.org/stable/c/cabfacbd5af09d3ae898ca224c4a1459e9bba15d