Use-After-Free Vulnerability in libsubcmd

Kernel Updated 02 Oct 2025

Summary

27/02/2022

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2022-1000468: libsubcmd: Fix use-after-free for realloc(..., 0). Affects Kernel versions >= 2f4ce5ec1d447beb42143a9653716a2ab025161e, < f8ba235c4927b5f970c868ac101ec42ca16c183a. No fix is published. How to fix ↓

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Background

libsubcmd is a library used in the Linux Kernel for handling subcommands. It provides functions for parsing and executing subcommands within a larger command-line interface. The library is an integral part of the Linux Kernel and is widely used in various Linux distributions. However, a use-after-free vulnerability has been discovered in libsubcmd, which can lead to potential security issues.

Vulnerability Detail

The use-after-free vulnerability in libsubcmd occurs when the realloc function is called with a size of 0. This can result in a use-after-free condition, where a pointer to a previously freed memory block is still being accessed. An attacker could potentially exploit this vulnerability to execute arbitrary code, escalate privileges, or cause a denial-of-service condition. The vulnerability was introduced in version 4.5 of the Linux Kernel and has been fixed in version 5.15.25.

How To Fix

No fixed version is published for this vulnerability.

To fix this vulnerability, it is recommended to update the Linux Kernel to version 5.15.25 or later. This can be done by applying the necessary patches or upgrading to a Linux distribution that includes the fixed version of the Kernel. It is important to keep the Kernel up to date to ensure the security and stability of the system.

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Workaround

There is no known workaround for this vulnerability. It is essential to apply the fix by updating the Linux Kernel.

Conclusion

The use-after-free vulnerability in libsubcmd can pose a significant security risk to systems running the affected versions of the Linux Kernel. It is crucial to update the Kernel to version 5.15.25 or later to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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