Cloudanix VulnDB

CVE-2026-80815

None

CVSS

—

EPSS

0.2%

Published

Sep 4, 2026

CISA due date

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Cloudanix analysis

Schedule a fix SSVC: Track

A bug in how certain USB audio devices talk to Linux can cause the whole computer to suddenly crash when the device is plugged in or the system wakes up.

Exploitation
Local Privilege
Attacker needs
Local User
Complexity
Low
Impact
Denial Of Service
Component
OS kernel
Class
Memory Corruption
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Incorrect reuse of a shared USB URB and failure to initialize a completion structure in the scarlett2 ALSA driver leads to a kernel crash when wait_for_completion_timeout dereferences a zeroed wait.head after the notification endpoint setup is skipped.

Why it matters to the business

Systems using affected Focusrite Scarlett audio interfaces may experience sudden kernel panics during driver initialization or resume, causing audio functionality loss and potential data corruption in unsaved work.

How an attack unfolds

An attacker with local access to a system containing a supported Scarlett2 device triggers the driver load path, causing the shared URB check to silently skip notification setup and leave cmd_done uninitialized; subsequent USB commands then panic the kernel via the uninitialized completion.

How to fix it

Update to a Linux kernel containing the private URB allocation, scarlett2_init_private initialization, scarlett2_cleanup_urb, private_resume callback, and reinit_completion changes; rebuild and reboot after installing the fixed kernel package for the distribution in use.

How to confirm the fix worked

Confirm the presence of scarlett2_init_private, scarlett2_cleanup_urb, and reinit_completion calls in the built kernel source or module; test device plug-in and suspend/resume cycles without kernel oops or panic.

Typical attack path

  1. Attach supported Scarlett2 USB audio device
  2. Trigger ALSA mixer initialization or system resume
  3. Driver reuses status URB and skips private notification URB allocation
  4. cmd_done remains zeroed
  5. scarlett2_usb_init issues command and waits on uninitialized completion
  6. Kernel dereferences invalid wait.head and panics

How to detect it

Review kernel logs for oops or panic messages referencing wait_for_completion_timeout, scarlett2_usb_init, or ALSA mixer status URB around device attach or resume events; correlate with dmesg entries showing scarlett2 driver load.

What your security team should do

  • Prioritize kernel updates on workstations or servers with Scarlett2 hardware attached
  • Monitor vendor kernel changelogs for the scarlett2 private URB fix
  • Temporarily blacklist the scarlett2 module on affected systems until patched if audio hardware is non-essential

The record

In the Linux kernel, the following vulnerability has been resolved: ALSA: scarlett2: Use a private URB for the notification endpoint scarlett2_init_notify() used mixer->urb, which snd_usb_mixer_status_create() allocates for the UAC2 status interrupt endpoint and mixer.c manages. On a device with that endpoint, the "already in use" check fires on the status URB and returns 0 for success without doing anything. No notification URB is submitted, and cmd_done is left zeroed because it is initialised past that check and nowhere else. scarlett2_usb_init() then issues SCARLETT2_USB_INIT_1 and wait_for_completion_timeout() would crash adding to the zeroed wait.head. Use a separate URB in scarlett2_data, as done for FCP, and initialise cmd_done in scarlett2_init_private(). mixer.c was also freeing the URB in snd_usb_mixer_free() and resubmitting it in snd_usb_mixer_activate(), so scarlett2 must now do both: add scarlett2_cleanup_urb(), called from private_free and private_suspend, and a private_resume callback to re-establish the URB after resume. scarlett2_init_notify() is reached from there, and the URB kill path in scarlett2_notify() completes cmd_done, leaving a stale count that would satisfy the next command's wait before the device ACKs. Use reinit_completion() to clear it. Also free the URB if the transfer buffer allocation fails, and both if usb_submit_urb() fails. Move scarlett2_init_notify() up next to scarlett2_cleanup_urb() so scarlett2_init_private() can reference it without a forward declaration.

Affected packages

Ecosystem Package Introduced Fixed