Medium severity · published Sep 8, 2026
CVE-2026-66816
Microsoft SQL Server Security Feature Bypass Vulnerability
6.5
CVSS
1%
EPSS
No
On KEV
Description
Insufficient logging in SQL Server allows an authorized attacker to bypass a security feature over a network.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 62% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Microsoft SQL Server 2022 (CU 26) · Microsoft
16.0.0.0 before 16.0.4275.2 · source: vendor
MS
Microsoft SQL Server 2022 (GDR) · Microsoft
16.0.0 before 16.0.1200.5 · source: vendor
MS
Microsoft SQL Server 2025 (CU8) · Microsoft
17.0.0.0 before 17.0.4085.5 · source: vendor
MS
Microsoft SQL Server 2025 for x64-based Systems (GDR) · Microsoft
17.0.1050.2 before 17.0.1135.8 · source: vendor
SS
Sql Server 2022 · Microsoft
before 16.0.1200.5; 16.0.4003.1 before 16.0.4275.2 · source: NVD
SS
Sql Server 2025 · Microsoft
before 17.0.1135.8; 17.0.4006.2 before 17.0.4085.5 · source: NVD
Affected product
MS
Microsoft SQL Server 2022 (CU 26)
Microsoft
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-66816
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-66816
vendor-advisory
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66816
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