SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-43379

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.

CRITICAL 9.8EPSS 0.44%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.44% probability · 38th percentile
CISA KEV
Not listed
Weakness
CWE-416
Affected
linux/linux kernel
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.