CVE-2026-66814 Microsoft SQL Server Elevation of Privilege Vulnerability

High 8.8 Published 8 Sep 2026 Updated 14 Oct 2026

An authorized attacker can elevate privileges in Microsoft SQL Server due to insufficient access control granularity.

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

What is CVE-2026-66814?

CVE-2026-66814 is a high-severity vulnerability in Microsoft Sql Server 2017, published on 8 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Insufficient granularity of access control in SQL Server allows an authorized attacker to elevate privileges over a network.

Weakness: CWE-1220

Which versions are affected by CVE-2026-66814?

It affects 4 products.

Products include Microsoft Sql Server 2017, Microsoft Sql Server 2019, Microsoft Sql Server 2022, Microsoft Sql Server 2025.

How do I fix CVE-2026-66814?

No fix has been published for CVE-2026-66814 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-66814 being exploited?

There is no known exploitation of CVE-2026-66814 in the wild and no public exploit code.

All Microsoft Sql Server 2017 vulnerabilities

Sources

Also known as GHSA-jv4w-r899-fr8h.