Race Condition Vulnerability in Linux Kernel's Huge Page Management
Summary
CVE-2025-38085: In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race huge_pmd_unshare() drops a reference on a page table that may have previously been shared across pro... Affects linux versions 5.10.103-1 – 6.9.9-1. No fix is published. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
The Linux kernel is the core component of many operating systems, providing essential services for hardware and software interaction. It supports various functionalities, including process management, memory management, and device control. This vulnerability affects the handling of huge pages, which are used to improve memory management efficiency. The issue arises from a race condition in the huge_pmd_unshare() function, which can lead to unexpected behavior in concurrent processes.
Vulnerability Detail
In the Linux kernel, the huge_pmd_unshare() function drops a reference on a page table that may have been shared across processes. This can inadvertently convert it into a normal page table used by another process, allowing unrelated Virtual Memory Areas (VMAs) to be installed. If this occurs during a concurrent gup_fast() operation, it could lead to gup_fast() traversing the page tables of a different process. Although this does not immediately result in kernel memory corruption, it creates a confusing and unpredictable situation that could have serious implications.
How To Fix
No fixed version is published for this vulnerability.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
Currently, there are no specific workarounds mentioned for this vulnerability. It is recommended to apply the patch as soon as it becomes available.
Conclusion
CVE-2025-38085 is a significant vulnerability in the Linux kernel that arises from a race condition in memory management. It is crucial for users to update their systems to mitigate potential risks. Monitoring tools like Vulert can help keep track of vulnerabilities in open-source software.
See every vulnerability recorded for linux →
FAQ
CVE-2025-38085 is a vulnerability in the Linux kernel related to a race condition in the huge_pmd_unshare() function, which can lead to unexpected behavior in memory management.
While it does not immediately cause memory corruption, it can lead to unpredictable behavior in concurrent processes, potentially affecting system stability.
You should update your Linux package to the latest version that includes the fix for this vulnerability.
Yes, you can use Vulert, which monitors open-source vulnerabilities in your software using a manifest file like package-lock.json. You can check for affected applications using the Vulert playground.
You can find detailed information about CVE-2025-38085 in the official Linux kernel documentation and security advisories.
Related vulnerabilities
Recent vulnerabilities recorded for linux.
