Vulnerability in mptcp: never allow the PM to close a listener subflow

Kernel Updated 02 Oct 2025

Summary

27/12/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1002745: mptcp: never allow the PM to close a listener subflow. Affects Kernel versions >= 740d798e8767d8a449902b1a1bbc70facfce19b5, < 1456a0004cc54c58adb2501cb0c95dc8b3c83e9e. No fix is published. How to fix ↓

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Background

The Kernel package is an integral part of the Linux operating system. It provides the core functionality and acts as a bridge between the hardware and software layers. The mptcp module in the Kernel enables the use of Multipath TCP, which allows for the simultaneous use of multiple network paths for a single TCP connection. This feature enhances performance, reliability, and resilience. However, a vulnerability has been discovered in the mptcp module that could potentially be exploited by attackers.

Vulnerability Detail

The vulnerability in the mptcp module allows the Path Manager (PM) to close a listener subflow. This behavior can be abused by malicious actors to disrupt network connections and potentially launch further attacks. The impact and attack plausibility of this vulnerability have not been proven yet, but it poses a potential risk to the stability and security of systems utilizing Multipath TCP. The vulnerability was introduced in version v5.13 of the Linux Kernel and has been fixed in version v5.15.11.

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 v5.15.11 or later. This can be done by obtaining the latest stable release from the official Linux Kernel repository and following the installation instructions provided. It is crucial to keep the Kernel up to date to ensure the security and stability of the system.

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Workaround

There is no specific workaround mentioned for this vulnerability.

Conclusion

The vulnerability in the mptcp module of the Linux Kernel can potentially be exploited to disrupt network connections. It is crucial to update the Kernel to version v5.15.11 or later to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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