Bug 2468199 (CVE-2026-43379)

Summary: CVE-2026-43379 kernel: ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in ksmbd, a component of the Linux kernel. A race condition exists where a pointer to `opinfo` is accessed after its associated memory may have been freed by a concurrent operation. This use-after-free vulnerability can lead to memory corruption, potentially causing system instability or a denial of service (DoS).
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Description OSIDB Bzimport 2026-05-08 15:04:20 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()

opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being
accessed after rcu_read_unlock() has been called. This creates a
race condition where the memory could be freed by a concurrent
writer between the unlock and the subsequent pointer dereferences
(opinfo->is_lease, etc.), leading to a use-after-free.
Comment 1 Keith Grant 2026-05-08 21:12:08 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026050832-CVE-2026-43379-1808@gregkh/T