CVE-2026-23432
Use-After-Free in Linux mshv_map_user_memory Causes Kernel Panic
Publication date: 2026-04-03
Last updated on: 2026-04-27
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 6.19 |
| linux | linux_kernel | From 6.19.1 (inc) to 6.19.10 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-416 | The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability is a use-after-free issue in the Linux kernel's mshv_map_user_memory function. Specifically, when an error occurs, the code calls vfree() directly on a memory region without properly unregistering the MMU notifier. Later, when userspace unmaps this memory, the still-registered notifier accesses the already freed memory region, leading to a use-after-free condition that can cause a kernel panic.
The fix involves replacing the direct call to vfree() with mshv_partition_put(), which correctly unregisters the MMU notifier before freeing the memory region, preventing the use-after-free scenario.
How can this vulnerability impact me? :
This vulnerability can lead to a kernel panic due to a use-after-free condition in the Linux kernel. A kernel panic can cause the system to crash or become unstable, potentially leading to denial of service. This could disrupt normal operations and affect system availability.
What immediate steps should I take to mitigate this vulnerability?
The vulnerability is fixed by replacing the direct call to vfree() with mshv_partition_put() in the mshv_map_user_memory() function to properly unregister the MMU notifier before freeing the memory region.
To mitigate this vulnerability immediately, you should update your Linux kernel to a version that includes this fix.