mISDN: Use-after-free vulnerability in HFC_cleanup()

Kernel Updated 02 Oct 2025

Summary

03/08/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1001303: mISDN: fix possible use-after-free in HFC_cleanup(). Affects Kernel versions < b7ee9ae1e0cf55a037c4a99af2acc5d78cb7802d. No fix is published. How to fix ↓

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Background

mISDN is a module in the Linux Kernel that provides support for ISDN (Integrated Services Digital Network) devices. It allows communication between computers and ISDN networks. The HFC_cleanup() function is responsible for cleaning up resources associated with the HFC (Hybrid Function Chip) device. However, a use-after-free vulnerability has been discovered in this function.

Vulnerability Detail

The use-after-free vulnerability in HFC_cleanup() occurs when the function attempts to access memory that has already been freed. An attacker could potentially exploit this vulnerability to execute arbitrary code or cause a denial-of-service condition. The impact and attack plausibility of this vulnerability have not been proven yet.

How To Fix

No fixed version is published for this vulnerability.

The use-after-free vulnerability in HFC_cleanup() has been fixed in Linux Kernel version v5.10.51 by commit b7ee9ae1e0cf55a037c4a99af2acc5d78cb7802d. To fix this vulnerability, users should update their Linux Kernel to version v5.10.51 or later.

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Conclusion

The use-after-free vulnerability in HFC_cleanup() in mISDN has been addressed in Linux Kernel version v5.10.51. Users are advised to update their Linux Kernel to this version or later to mitigate the vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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