ALSA: gus - Null Pointer Dereference on Pointer Block

Kernel Updated 02 Oct 2025

Summary

29/11/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1002266: ALSA: gus: fix null pointer dereference on pointer block. Affects Kernel versions < c6d2cefdd05c4810c416fb8d384b5c377bd977bc. No fix is published. How to fix ↓

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Background

ALSA (Advanced Linux Sound Architecture) is a software framework and part of the Linux kernel that provides an API for sound card drivers. The gus module in ALSA is responsible for supporting the Gravis Ultrasound sound card. This vulnerability in the gus module allows for a null pointer dereference on the pointer block, leading to a potential system crash or privilege escalation.

Vulnerability Detail

The vulnerability arises from a null pointer dereference on the pointer block in the gus module of ALSA. An attacker could exploit this vulnerability by sending specially crafted input to a system with a Gravis Ultrasound sound card, causing a null pointer dereference and potentially crashing the system or gaining elevated privileges. This vulnerability has been fixed in Linux Kernel version v5.4.162 by commit c6d2cefdd05c4810c416fb8d384b5c377bd977bc.

How To Fix

No fixed version is published for this vulnerability.

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Workaround

There is no known workaround for this vulnerability. It is recommended to apply the fix by updating the Linux Kernel as mentioned above.

Conclusion

The ALSA gus module vulnerability allows for a null pointer dereference on the pointer block, potentially leading to system crashes or privilege escalation. It is crucial to update the Linux Kernel to version v5.4.162 or later to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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