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

criticalCVSS 9.8CVE-2026-78445

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

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: critical — CVSS 9.8
Published: 2026-09-08
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78445

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-784450.91% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 58% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-78445	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownexploitedNCSC-2026-0353 [1.01] [M/H] Kwetsbaarheden verholpen in Microsoft Windowsncsc-nl
unknownNCSC-2026-0353 [1.00] [M/H] Kwetsbaarheden verholpen in Microsoft Windowsncsc-nl
criticalCVE-2026-78445: Use after free in Windows Services for NFS ONCRPC XDR Driver allows an unauthorized attacker t…nvd

Recent advisories for Windows Services for

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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highCVE-2026-83989: Out-of-bounds read in Windows Services for NFS ONCRPC XDR Driver allows an unauthorized attack…nvd · 2026-09-08