CVE-2026-46179

What it actually does

This is a local denial-of-service vulnerability in the Linux kernel Sound Open Firmware (SOF) ASoC compressed-audio stream handling. The vulnerable code reports the current compressed-stream pointer by dividing an I/O position by stream parameters such as channel count and container byte size. Those values default to zero before stream parameters are configured, so a local user able to interact with the affected compressed-audio interface can trigger a divide-by-zero condition in kernel context. The likely result is an oops, kernel panic, or audio subsystem failure that can degrade or halt system availability. The flaw does not provide a direct confidentiality or integrity impact and is not remotely exploitable based on the published characteristics.

Why it matters to the business

Successful exploitation can crash or destabilize Linux systems that expose the affected SOF compressed-audio functionality to local users or workloads. This can interrupt endpoints, kiosks, embedded Linux devices, developer workstations, or appliances that rely on audio hardware using SOF drivers. Because exploitation requires local privileges and there is no known public exploit or KEV listing, broad internet-scale risk is low, but systems with untrusted local users, shared workstations, container escape-adjacent device exposure, or user-accessible audio devices should still treat the issue as an availability risk.

How an attack unfolds

An attacker first obtains local code execution as a regular user on a system running a vulnerable Linux kernel with the SOF ASoC compressed-audio path available. The attacker opens or otherwise interacts with a compressed-audio stream device before valid stream parameters are configured. They then request the stream pointer or state in a way that reaches the vulnerable SOF pointer-reporting routine. Because the channel count and container-byte values remain zero, the kernel performs a division by zero while handling the request. This occurs in kernel context and can produce a kernel oops or panic, resulting in a local denial of service. There is no indication from the provided data that this vulnerability enables privilege escalation, remote code execution, data theft, or ransomware activity.

How to fix it

Apply the Linux kernel update from the operating system or device vendor that includes the fix for the SOF ASoC compressed-stream pointer validation issue. The corrected behavior validates that channel count and container byte size are nonzero before performing pointer calculations and returns an error for unconfigured streams. No exact fixed package versions were provided, so track the advisory from the relevant distribution, kernel vendor, appliance vendor, or embedded platform supplier. Where immediate patching is not possible, reduce exposure by restricting local shell access, limiting access to audio device nodes, disabling unused SOF/audio functionality, removing untrusted users from audio-related groups, and avoiding passthrough of audio devices into containers or sandboxed workloads unless required.

How to confirm the fix worked

Confirm that the running kernel version includes the vendor fix for the SOF ASoC compressed-stream pointer validation change. Validate using distribution package metadata, vendor advisories, or kernel changelogs rather than source presence alone. On Linux systems, compare `uname -a` and installed kernel package versions against the vendor-fixed release, then reboot into the updated kernel. Confirm that SOF-related modules and audio devices are still functioning after the update. For exposure validation, check whether SOF drivers are loaded and whether users or workloads can access audio device nodes such as `/dev/snd/*`. Avoid reproducing the divide-by-zero condition on production systems because successful validation of the vulnerable behavior may crash the host.

Typical attack path

1. Gain local access to a vulnerable Linux system as a low-privileged user.
2. Identify that the system has SOF/ASoC compressed-audio functionality and accessible audio device nodes.
3. Open or initialize a compressed-audio stream without fully configuring valid stream parameters.
4. Trigger a pointer/status operation on the unconfigured compressed stream.
5. Cause the kernel to divide by zero while calculating the compressed stream position.
6. Crash or destabilize the kernel or audio subsystem, producing a denial of service.

How to detect it

Look for evidence of local kernel crashes or oops events around ALSA, ASoC, SOF, or compressed-audio device access. Relevant sources include `journalctl -k`, `/var/log/kern.log`, `/var/log/messages`, `/var/log/syslog`, `dmesg`, pstore/ramoops records under `/sys/fs/pstore/`, kernel crash dumps, and audit logs showing access to `/dev/snd/*`. Correlate crash timestamps with local user sessions, process execution, container activity, and device-node access. Indicators are likely to be generic kernel-fault artifacts rather than unique attacker tooling because exploitation can be performed through normal audio APIs. Search for divide-by-zero exceptions, kernel oops or panic messages, SOF/ASoC driver references, ALSA compressed-stream references, and repeated audio device opens immediately before a system crash.

• divide error: 0000
• divide error
• Kernel panic - not syncing
• Oops: divide error
• RIP: 0010:sof_compr_pointer
• sof_compr_pointer
• snd_sof
• snd_sof_pci
• snd_sof_intel
• ASoC: SOF
• Sound Open Firmware
• ALSA
• compress_offload
• /dev/snd/
• /sys/fs/pstore/
• dmesg
• journalctl -k

What your security team should do

• Prioritize patching shared Linux workstations, multi-user systems, embedded devices, kiosks, and systems that expose `/dev/snd/*` or audio hardware to untrusted users or containers.
• Inventory systems using SOF/ASoC audio drivers by checking loaded modules, kernel logs, and hardware profiles.
• Restrict membership in audio-related groups and permissions on `/dev/snd/*` to only users and services that require audio access.
• Avoid passing host audio devices into containers, VMs, or sandboxed workloads unless explicitly needed and controlled.
• Monitor kernel logs for divide-by-zero, oops, or panic events involving SOF, ASoC, ALSA compressed audio, or `snd_sof` components.
• If unexplained crashes are observed on vulnerable systems, preserve kernel logs, pstore/ramoops data, crash dumps, and audit records before rebooting or reimaging.
• Because EPSS is low, there is no KEV listing, and no exploit maturity is reported, handle this as a targeted/local availability issue rather than an emergency internet-facing exposure.