CVE-2026-43379
ksmbd Use-After-Free in Linux Kernel
Publication date: 2026-05-08
Last updated on: 2026-05-19
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 | From 6.13 (inc) to 6.18.19 (exc) |
| linux | linux_kernel | From 6.19 (inc) to 6.19.9 (exc) |
| linux | linux_kernel | From 6.6.32 (inc) to 6.6.130 (exc) |
| linux | linux_kernel | From 6.9 (inc) to 6.12.78 (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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.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 ksmbd component, specifically in the smb_lazy_parent_lease_break_close() function.
The problem occurs because an opinfo pointer, obtained via rcu_dereference(fp->f_opinfo), is accessed after rcu_read_unlock() has been called. This creates a race condition where the memory pointed to by opinfo could be freed by another concurrent process before it is accessed, leading to use-after-free errors.
How can this vulnerability impact me? :
The use-after-free vulnerability can lead to undefined behavior such as system crashes, data corruption, or potential execution of arbitrary code if exploited.
Because it involves a race condition in kernel memory management, an attacker might exploit this to cause denial of service or escalate privileges on the affected system.