net: cdc_eem: fix tx fixup skb leak in Kernel

Kernel Updated 02 Oct 2025

Summary

30/06/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1000990: net: cdc_eem: fix tx fixup skb leak. Affects Kernel versions >= 9f722c0978b04acba209f8ca1896ad05814bc3a3, < 05b2b9f7d24b5663d9b47427fe1555bdafd3ea02. No fix is published. How to fix ↓

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Background

The Kernel is a crucial component of the Linux operating system, responsible for managing system resources and facilitating communication between hardware and software. It provides essential functionality for the proper functioning of the system. The cdc_eem module in the Kernel is responsible for supporting the Communication Device Class (CDC) Ethernet Emulation Model (EEM) over USB. This module allows devices to communicate over USB as if they were connected via Ethernet. However, a vulnerability has been discovered in the cdc_eem module that can lead to a memory leak when fixing transmit (tx) fixup socket buffer (skb). This vulnerability can potentially be exploited by attackers to exhaust system memory and cause a denial-of-service (DoS) condition.

Vulnerability Detail

The vulnerability in the cdc_eem module arises from a memory leak when fixing the transmit fixup socket buffer. When this occurs, system memory is not properly released, leading to memory exhaustion over time. An attacker can exploit this vulnerability by repeatedly triggering the tx fixup skb fix, causing the system to run out of memory and resulting in a DoS condition. This vulnerability was introduced in version v2.6.30 of the Kernel and has been fixed in version v5.10.46. It is important to update to the fixed version to mitigate the risk of exploitation.

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 update the Kernel to the fixed version.

Conclusion

The cdc_eem module in the Kernel is vulnerable to a memory leak when fixing the transmit fixup socket buffer. This can lead to memory exhaustion and a denial-of-service condition. It is crucial to update the Kernel to version v5.10.46 or later to mitigate the risk of exploitation. For further support on vulnerability remediation, you can contact DevNack.com.

See every vulnerability recorded for Kernel →