CVE-2026-23364 ksmbd: Compare MACs in constant time

What is CVE-2026-23364?

CVE-2026-23364 is a high-severity vulnerability in Linux kernel, published on 25 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: Compare MACs in constant time

To prevent timing attacks, MAC comparisons need to be constant-time. Replace the memcmp() with the correct function, crypto_memneq().

Which versions are affected by CVE-2026-23364?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-23364?

Apply the vendor's patch.

Is CVE-2026-23364 being exploited?

There is no known exploitation of CVE-2026-23364 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-23364, DEBIAN-CVE-2026-23364, GHSA-4mmg-5v66-42gx, ROOT-OS-DEBIAN-12-CVE-2026-23364, ROOT-OS-DEBIAN-13-CVE-2026-23364, ROOT-OS-UBUNTU-2204-CVE-2026-23364 and 2 more.