SB20260824173 - Out-of-bounds write in Linux kernel usb

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds write (CVE-ID: CVE-2026-74640)

CWE-ID: CWE-787 - Out-of-bounds write

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 overwrite kernel memory and cause a denial of service.

The vulnerability exists due to an out-of-bounds write in fcp_meter_ctl_get() when reading ALSA FCP controls with an oversized user-defined meter map. A local user can read a crafted control value to overwrite kernel memory and cause a denial of service.

Installing the oversized meter map requires CAP_SYS_RAWIO, but the created control can later be read by an unprivileged process through /dev/snd/controlC0.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/620f1e52a46f604635efd0fb78138afd6a513b5d
• https://git.kernel.org/stable/c/bb30e35c36ed00f24fa39aded811f64230a913b0
• https://git.kernel.org/stable/c/bb61dc2ae59026f76db26e1909746908bc5b6f31