isdn: mISDN: Fix sleeping function called from invalid context

Kernel Updated 02 Oct 2025

Summary

28/10/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1001814: isdn: mISDN: Fix sleeping function called from invalid context. Affects Kernel versions < 4054b869dc263228d30a4755800b78f0f2ba0c89. No fix is published. How to fix ↓

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Background

The isdn package is a part of the Linux Kernel ecosystem. It provides support for Integrated Services Digital Network (ISDN) devices. ISDN is a set of communication standards for transmitting voice, video, and data over digital telephone lines. The mISDN subsystem within the isdn package is responsible for managing ISDN devices and their associated drivers.

This vulnerability in the mISDN subsystem involves a sleeping function being called from an invalid context. Sleeping functions are used to pause the execution of a program for a specified period of time. However, calling a sleeping function from an invalid context can lead to various issues, including system instability, crashes, and potential security vulnerabilities.

Vulnerability Detail

The vulnerability in the mISDN subsystem arises from a sleeping function being called from an invalid context. When a sleeping function is called from an invalid context, it can disrupt the normal flow of execution and cause unexpected behavior. In the context of this vulnerability, it is likely that the sleeping function is being called from a context where it is not allowed or expected, potentially leading to system instability or security vulnerabilities.

The impact and attack plausibility of this vulnerability have not been proven yet. However, it is important to address this issue to ensure the stability and security of the system.

This vulnerability has been fixed in Linux Kernel version v5.4.156 by commit 4054b869dc263228d30a4755800b78f0f2ba0c89.

How To Fix

No fixed version is published for this vulnerability.

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Conclusion

The isdn package in the Linux Kernel is vulnerable to a sleeping function being called from an invalid context within the mISDN subsystem. This vulnerability can potentially lead to system instability or security vulnerabilities. It is recommended to update the Linux Kernel to version v5.4.156 or later to fix this issue. For further support on vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for Kernel →