SB2026110855 - Use-after-free in Linux kernel usb line6

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-99271)

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 potentially cause a denial of service by triggering a read from freed kernel memory.

The vulnerability exists due to a use-after-free in the Linux kernel ALSA Line6 USB audio driver when playback accesses a capture buffer after all capture streams have been closed. A local user can trigger playback, such as through the impulse test signal volume control, after the capture buffer is released to cause submit_audio_out_urb() to dereference the stale prev_fbuf pointer, potentially causing a denial of service.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/22c82f33ff0b68d37041adf1dea5533a5863cd31
• https://git.kernel.org/stable/c/862d9268f40a6e10cef24eb226e738fb69ce8aa7
• https://git.kernel.org/stable/c/aa118c8f61d59387961d58ffae831c5259a9f222