Critical Vulnerability in Linux Kernel: tcp_metrics Lock Dependency Issue
Summary
DEBIAN-CVE-2025-40075: In the Linux kernel, the following vulnerability has been resolved: tcp_metrics: use dst_dev_net_rcu() Replace three dst_dev() with a lockdep enabled helper. Affects linux versions 5.10.103-1 – 6.9.9-1. No fix is published. How to fix ↓
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Background
The Linux kernel is the core component of many operating systems, providing essential services for hardware management and system resource allocation. It is known for its stability, performance, and security features. However, vulnerabilities can arise, impacting the integrity and security of systems that rely on it. This specific vulnerability pertains to the tcp_metrics functionality, which is responsible for managing TCP connection metrics.
Vulnerability Detail
In the Linux kernel, a vulnerability has been identified in the tcp_metrics component, where the use of dst_dev() was not properly managed, leading to potential lock dependency issues. This flaw could allow for improper handling of network metrics, potentially leading to system instability or security breaches. The vulnerability has been resolved by replacing three instances of dst_dev() with a lockdep enabled helper, ensuring better management of lock dependencies.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
Currently, no specific workarounds have been provided for this vulnerability. It is recommended to apply the patch as soon as it becomes available.
Conclusion
The vulnerability CVE-2025-40075 in the Linux kernel's tcp_metrics functionality poses a risk of system instability and security issues. Users are advised to update their systems to the latest patched version to mitigate these risks. Utilizing tools like Vulert can help monitor and alert for such vulnerabilities in real-time.
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FAQ
CVE-2025-40075 is a vulnerability in the Linux kernel related to the tcp_metrics functionality, which could lead to improper handling of network metrics.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in your software. By uploading your manifest file like package-lock.json, you can check for vulnerabilities in real-time.
The vulnerability could lead to system instability or security breaches due to improper management of TCP connection metrics.
Yes, a patch has been released that replaces the problematic dst_dev() calls with a lockdep enabled helper. Users should update their Linux kernel package to the latest version.
You can update your Linux kernel by running the command 'sudo apt-get update && sudo apt-get upgrade linux' in your terminal.
References
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