Critical Assertion Failure in Linux Kernel's Btrfs Package: CVE-2025-38503
Summary
CVE-2025-38503: In the Linux kernel, the following vulnerability has been resolved: btrfs: fix assertion when building free space tree When building the free space tree with the block group tree feature enabled, we can hit an assertion... 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 and software interaction. It supports various file systems, including Btrfs, which is known for its advanced features like snapshots, dynamic inode allocation, and integrated volume management. This vulnerability affects the Btrfs file system, specifically when building the free space tree with the block group tree feature enabled, potentially leading to system crashes.
Vulnerability Detail
CVE-2025-38503 is a critical vulnerability in the Linux kernel's Btrfs file system that arises from an assertion failure during the construction of the free space tree. This issue occurs when processing an empty block group that lacks allocated extents, leading to a kernel panic. The vulnerability can result in system instability and data loss, as it may cause the kernel to crash unexpectedly. The root cause lies in the improper handling of block groups without items, which can trigger an assertion failure in the code responsible for managing free space.
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. Users are advised to apply the available patches as soon as possible to mitigate the risk.
Conclusion
CVE-2025-38503 is a significant vulnerability in the Linux kernel's Btrfs file system that can lead to critical system failures. Users are strongly encouraged to update their systems to the patched versions to ensure stability and security. Utilizing tools like Vulert can help monitor for such vulnerabilities in real-time.
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FAQ
CVE-2025-38503 is a vulnerability in the Linux kernel's Btrfs file system that can cause assertion failures and kernel crashes when processing empty block groups.
You can use the Vulert platform to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check if your application is affected without requiring any signup.
The vulnerability can lead to system crashes and potential data loss, affecting the stability and reliability of systems using the Btrfs file system.
Yes, patches are available for Debian 12 and 13. Users should update to the fixed versions to mitigate the risk.
While there are no specific workarounds, it is crucial to prioritize updating your system to the patched version to avoid potential crashes and data loss.
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