CVE-2026-43379
Linux Kernel use-after-free
- Published8 May 2026
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 breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HAffected products
Remediation
- https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6
- https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619
- https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086
- https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399
- https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25
References
- https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6
- https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619
- https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086
- https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399
- https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25
Related CVEs
Recent high-severity vulnerabilities sharing a weakness type.
Frequently asked
Is CVE-2026-43379 being actively exploited?
CVE-2026-43379 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.65%.
How severe is CVE-2026-43379?
CVE-2026-43379 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.65% probability of exploitation.
Which products are affected by CVE-2026-43379?
Affected products include Linux Kernel.
How do I fix CVE-2026-43379?
Upgrade affected software to a fixed version, for example Linux Kernel 6.18.19 or later, then confirm no affected versions remain in your inventory.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2026-43379 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.