Critical severity · published May 8, 2026
CVE-2026-43376
ksmbd: fix use-after-free by using call_rcu() for oplock_info
9.8
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
6.6.88 before 6.6.130; 6.12.25 before 6.12.78; 6.14.4 before 6.15; 6.15.1 before 6.18.19; 6.19 before 6.19.9; 6.15; +8 more · source: NVD
LI
Linux · Linux
296cb5457cc6f4a754c4ae29855f8a253d52bcc6 before 302fef75512b2c8329a3f5efab1ae7ba2562387a; d54ab1520d43e95f9b2e22d7a05fc9614192e5a5 before 08aa9f3c8cf4d0bee44df540dfe34e8d64069f2c; 18b4fac5ef17f77fed9417d22210ceafd6525fc7 before 1d6abf145615dbfe267ce3b0a271f95e3780e18e; 18b4fac5ef17f77fed9417d22210ceafd6525fc7 before ce8507ee82c888126d8e7565e27c016308d24cde; 18b4fac5ef17f77fed9417d22210ceafd6525fc7 before 1dfd062caa165ec9d7ee0823087930f3ab8a6294; d73686367ad68534257cd88a36ca3c52cb8b81d8; +4 more · source: vendor