SB20260508102 - NULL pointer dereference in Linux kernel gadget function driver

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-43421)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to a null pointer dereference in the f_ncm usb gadget network device lifecycle handling when disconnecting or unbinding the gadget device. A local user can trigger a crafted gadget disconnect or unbind sequence to cause a denial of service.

The issue occurs because the network device can outlive its parent gadget device, leaving dangling sysfs links.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/85acaba2f42b557499bab3608307f17bf13beb69
• https://git.kernel.org/stable/c/93f116c3393a22acab96ad1bef12b2572eb80ca4
• https://git.kernel.org/stable/c/e584cb58a2ea7ff4d3a4bc43d5ca512ed3ecb77d
• https://git.kernel.org/stable/c/ec35c1969650e7cb6c8a91020e568ed46e3551b0