CVE-2026-78445 Windows Services for NFS ONCRPC XDR Driver Remote Code Execution Vulnerability

Critical 9.8 Published 8 Sep 2026 Updated 14 Oct 2026

An attacker can execute arbitrary code remotely via a use-after-free flaw in the Windows NFS ONCRPC XDR driver.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-78445?

CVE-2026-78445 is a critical use after free vulnerability in Microsoft Windows Server 2012, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Use after free in Windows Services for NFS ONCRPC XDR Driver allows an unauthorized attacker to execute code over a network.

Weakness: CWE-416

Which versions are affected by CVE-2026-78445?

It affects 5 products.

Products include Microsoft Windows Server 2012, Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 2022, Microsoft Windows Server 2025.

How do I fix CVE-2026-78445?

No fix has been published for CVE-2026-78445 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2026-78445 being exploited?

There is no known exploitation of CVE-2026-78445 in the wild and no public exploit code.

All Microsoft Windows Server 2012 vulnerabilities

Sources

Also known as GHSA-xfjp-65r5-5w3m.