netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbage value

Kernel Updated 02 Oct 2025

Summary

14/11/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1002165: netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbage value. Affects Kernel versions >= 68983a354a655c35d3fb204489d383a2a051fda7, < 902c0b1887522a099aa4e1e6b4b476c2fe5dd13e. No fix is published. How to fix ↓

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Background

The netfilter package is a component of the Linux Kernel that provides a framework for packet filtering and network address translation. It allows administrators to define rules and policies for network traffic. The xt_IDLETIMER module is a part of netfilter that provides a timer-based mechanism to match idle connections. This module is vulnerable to a panic condition when the timer_type parameter is set to a garbage value.

Vulnerability Detail

The vulnerability in the xt_IDLETIMER module arises when an attacker sets the timer_type parameter to a garbage value. This can lead to a panic condition, causing the system to crash. The impact of this vulnerability is a denial-of-service (DoS) attack, as it allows an attacker to crash the system by triggering the panic condition. The vulnerability was introduced in Linux Kernel version v5.7 and is fixed in version v5.15.

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 or later. This update includes the commit 902c0b1887522a099aa4e1e6b4b476c2fe5dd13e, which addresses the issue. Users can obtain the updated kernel from the official Linux Kernel repository.

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Workaround

There is no known workaround for this vulnerability. It is necessary to update the Linux Kernel to the fixed version.

Conclusion

The netfilter xt_IDLETIMER module in the Linux Kernel is vulnerable to a panic condition when the timer_type parameter is set to a garbage value. This can lead to a system crash, resulting in a denial-of-service (DoS) attack. It is crucial to update the Linux Kernel to version v5.15 or later to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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