Use-After-Free Vulnerability in Linux Kernel's ksmbd Package
Summary
CVE-2025-37899: In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in session logoff The sess->user object can currently be in use by another thread, for example if another connection has sent... Affects linux versions 6.1.106-1 – 6.9.9-1. No fix is published. How to fix ↓
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Background
The Linux kernel is a core component of many operating systems, providing essential services for hardware management and system resources. The ksmbd module allows for SMB (Server Message Block) protocol support, enabling file sharing and printing services over a network. This module is critical for systems that require interoperability with Windows environments. However, it is susceptible to vulnerabilities that can lead to security breaches, such as the use-after-free issue identified in CVE-2025-37899.
Vulnerability Detail
CVE-2025-37899 is a use-after-free vulnerability in the ksmbd module of the Linux kernel. This vulnerability arises when the sess->user object is freed while still being accessed by another thread. Specifically, if a session setup request is sent to bind to a session that is in the process of being freed, it can lead to undefined behavior, potentially allowing an attacker to execute arbitrary code or cause a denial of service. The vulnerability highlights the importance of proper memory management in multithreaded environments.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
Currently, there are no specific workarounds provided for this vulnerability. It is advisable to apply the patch as soon as it becomes available to mitigate the risk.
Conclusion
CVE-2025-37899 represents a significant security risk within the ksmbd module of the Linux kernel, emphasizing the need for timely updates and vigilant monitoring of vulnerabilities. Users are encouraged to apply the necessary patches and utilize tools like Vulert for ongoing vulnerability management.
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FAQ
CVE-2025-37899 is a use-after-free vulnerability in the ksmbd module of the Linux kernel, which can lead to security risks if exploited.
If exploited, this vulnerability could allow an attacker to execute arbitrary code or cause a denial of service, compromising system integrity.
You can use Vulert to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check if your application is affected by this vulnerability.
Yes, a patch is available. It is recommended to update your Linux package to the latest version to mitigate the vulnerability.
While there are no specific workarounds, it is crucial to prioritize applying the patch as soon as possible to protect your system.
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