SB2026080768 - Use-after-free in Linux kernel brcm80211 brcmfmac driver

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-64586)

CWE-ID: CWE-416 - Use After Free

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 use-after-free in the brcmfmac bus_reset work handling when a reset is scheduled during device removal. A local user can trigger a bus reset through the debugfs "reset" entry to cause a denial of service.

The issue affects shared bus_reset work across PCIe, SDIO, and USB removal paths, and brcmf_fw_crashed() could also be triggered before driver attachment completed.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/177a25be1195f8bdc6160ba5f1a5699f7041c985
• https://git.kernel.org/stable/c/43b25879f004c98defa2776bedc6ca4763c51945