SB20260815215 - NULL pointer dereference in Linux kernel sched

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-74266)

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 sch_dualpi2 queue discipline when processing packet queue peek operations after deferred packet drops. A local user can trigger packet processing that causes the parent qlen_notify callback to deactivate a class incorrectly to cause a denial of service.

The issue occurs when the queue length temporarily drops to zero during peek even though one packet still remains queued.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/15cd0c93bf4f892d66bc7a93667e2357b5673365
• https://git.kernel.org/stable/c/466f29477cae2bd1982a066d518a9b20c5a37924
• https://git.kernel.org/stable/c/bd851b10daee7199a658458b8ce250e95a334500