CVE-2026-43376

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free by using call_rcu() for oplock_info ksmbd currently frees oplock_info immediately using kfree(), even though it is accessed under RCU read-side critical sections in places like opinfo_get() and proc_show_files(). Since there is no RCU grace period delay between nullifying the pointer and freeing the memory, a reader can still access oplock_info structure after it has been freed. This can leads to a use-after-free especially in opinfo_get() where atomic_inc_not_zero() is called on already freed memory. Fix this by switching to deferred freeing using call_rcu().

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/08aa9f3c8cf4d0bee44df540dfe34e8d64069f2c	Patch
https://git.kernel.org/stable/c/1d6abf145615dbfe267ce3b0a271f95e3780e18e	Patch
https://git.kernel.org/stable/c/1dfd062caa165ec9d7ee0823087930f3ab8a6294	Patch
https://git.kernel.org/stable/c/302fef75512b2c8329a3f5efab1ae7ba2562387a	Patch
https://git.kernel.org/stable/c/ce8507ee82c888126d8e7565e27c016308d24cde	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.15:-::::::
	cpe:2.3:o:linux:linux_kernel:6.15:rc3::::::
	cpe:2.3:o:linux:linux_kernel:6.15:rc4::::::
	cpe:2.3:o:linux:linux_kernel:6.15:rc5::::::
	cpe:2.3:o:linux:linux_kernel:6.15:rc6::::::
	cpe:2.3:o:linux:linux_kernel:6.15:rc7::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::

History

No history.

Information

Published : 2026-05-08 15:16

Updated : 2026-06-17 10:49

NVD link : CVE-2026-43376

Mitre link : CVE-2026-43376

CVE.ORG link : CVE-2026-43376

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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