Use After Free Vulnerability in net: macb

Kernel Updated 02 Oct 2025

Summary

19/10/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1001752: net: macb: fix use after free on rmmod. Affects Kernel versions < 4ad6f2d23b0f6ac0d3e5f3102a4256d1c86c90f5. No fix is published. How to fix ↓

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Background

The net: macb package is a network driver for the MACB Ethernet controller found in various embedded systems. It provides functionality for handling network communication and is a part of the Linux Kernel. The vulnerability in question is a use after free issue that occurs when the package is unloaded (rmmod).

Vulnerability Detail

The use after free vulnerability in net: macb arises when the package is unloaded, leading to a situation where a pointer is accessed after the memory it points to has been freed. This can result in various consequences, including crashes, privilege escalation, or the execution of arbitrary code by an attacker. The vulnerability has been fixed in Linux Kernel version v5.14.9 by commit 4ad6f2d23b0f6ac0d3e5f3102a4256d1c86c90f5.

How To Fix

No fixed version is published for this vulnerability.

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Workaround

There is no specific workaround mentioned for this vulnerability. The recommended approach is to apply the fix by updating the Linux Kernel.

Conclusion

The use after free vulnerability in net: macb can have serious security implications. It is crucial to update the Linux Kernel to the fixed version to mitigate the risk. For further support on vulnerability remediation, please contact DevNack.com.

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