CVE-2025-71150 ksmbd: Fix refcount leak when invalid session is found on session lookup

What is CVE-2025-71150?

CVE-2025-71150 is a high-severity memory corruption vulnerability in Linux kernel, published on 23 Jan 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: Fix refcount leak when invalid session is found on session lookup

When a session is found but its state is not SMB2_SESSION_VALID, It indicates that no valid session was found, but it is missing to decrement the reference count acquired by the session lookup, which results in a reference count leak. This patch fixes the issue by explicitly calling ksmbd_user_session_put to release the reference to the session.

Which versions are affected by CVE-2025-71150?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2025-71150?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2025-71150 being exploited?

There is no known exploitation of CVE-2025-71150 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 AZL-78425, BELL-CVE-2025-71150, DEBIAN-CVE-2025-71150, GHSA-4mf3-frrh-jfqw, ROOT-OS-DEBIAN-12-CVE-2025-71150, ROOT-OS-DEBIAN-13-CVE-2025-71150 and 3 more.