CVE-2026-66820Network attack vector

Authenticated sysadmin escalation via SQL injection

Published Sep 8, 2026 · Updated Sep 10, 2026

SQL injection in Microsoft SQL Server allows remote authenticated users to gain SQL sysadmin privileges over a network. Microsoft has not disclosed the affected function, input, or SQL-construction operation beyond improper neutralization of special elements. Exploitation requires a valid SQL login with explicit permissions; success grants full administrative control of the SQL Server instance.

CVSS severity8.8
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

SQL injection in Microsoft SQL Server allows remote authenticated users to gain SQL sysadmin privileges over a network. Microsoft has not disclosed the affected function, input, or SQL-construction operation beyond improper neutralization of special elements. Exploitation requires a valid SQL login with explicit permissions; success grants full administrative control of the SQL Server instance.

The record

CVE
CVE-2026-66820
Published
Sep 8, 2026
Updated
Sep 10, 2026
Vendor
Microsoft
Product
Microsoft SQL Server 2022
Classifications
CWE-89, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=16.0.0.0 <16.0.4275.2
  2. Affected versionversion=16.0.0 <16.0.1200.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft SQL Server 2022version=16.0.0.0 <16.0.4275.2; version=16.0.0 <16.0.1200.5
Microsoft · Microsoft SQL Server 2019version=15.0.0.0 <15.0.4490.9; version=15.0.0 <15.0.2190.7
Microsoft · Microsoft SQL Server 2017version=14.0.0 <14.0.2130.4; version=14.0.0 <14.0.3550.4
Microsoft · Microsoft SQL Server 2025version=17.0.0.0 <17.0.4085.5; version=17.0.1050.2 <17.0.1135.8

Published CVSS scores

8.8MicrosoftCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-89Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo