CVE-2026-67643

Microsoft SQL Server Remote Code Execution Vulnerability

Published Sep 8, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
Description
Heap-based buffer overflow in SQL Server allows an unauthorized attacker to execute code over a network.

Analysis

AI-generated

Technical impact

This vulnerability is a heap‑based buffer overflow in Microsoft SQL Server that grants an authorized attacker the ability to execute code over the network. The overflow allows the attacker to inject and run arbitrary instructions within the SQL Server process, leading to full compromise of the database instance. The weakness is classified as CWE‑122.

Affected Systems

Affected products include Microsoft SQL Server 2022 cumulatively updated to CU 26 or its GDR release, Microsoft SQL Server 2025 CU 8, and Microsoft SQL Server 2025 for x64‑based systems in GDR. These specific versions are listed as impacted by the Microsoft security advisory.

Risk and Exploitability

The CVSS base score of 8.8 indicates a high severity. The EPSS score is not available, but the lack of a KEV listing suggests no publicly known exploitation yet. Based on the description, the likely attack vector is a network‑based attack carried out by an authenticated user with sufficient privileges, which can then take over the database process. The overall risk is high for environments that expose SQL Server to untrusted networks without adequate segmentation or access controls.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the latest Microsoft SQL Server cumulative update or GDR for the affected versions from the official Microsoft update guide.
  • Restrict network access to the SQL Server instances by configuring firewall rules and enabling secure connections only between trusted hosts.
  • Enable and monitor detailed audit logs for anomalous login attempts and payload activity.

Generated by OpenCVE AI on September 8, 2026 at 19:18 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Description Heap-based buffer overflow in SQL Server allows an authorized attacker to execute code over a network. Heap-based buffer overflow in SQL Server allows an unauthorized attacker to execute code over a network.
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}

cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Microsoft microsoft Sql Server 2022 (cu 26)
Microsoft microsoft Sql Server 2022 (gdr)
Microsoft microsoft Sql Server 2025 (cu8)
Microsoft microsoft Sql Server 2025 For X64-based Systems (gdr)
Vendors & Products Microsoft microsoft Sql Server 2022 (cu 26)
Microsoft microsoft Sql Server 2022 (gdr)
Microsoft microsoft Sql Server 2025 (cu8)
Microsoft microsoft Sql Server 2025 For X64-based Systems (gdr)
Type Values Removed Values Added
Description Heap-based buffer overflow in SQL Server allows an authorized attacker to execute code over a network.
Title Microsoft SQL Server Remote Code Execution Vulnerability
First Time appeared Microsoft
Microsoft sql Server 2022
Microsoft sql Server 2025
Weaknesses CWE-122
CPEs cpe:2.3:a:microsoft:sql_server_2022:*:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:sql_server_2025:*:*:*:*:*:*:x64:*
Vendors & Products Microsoft
Microsoft sql Server 2022
Microsoft sql Server 2025
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}

Weaknesses
  • CWE-122

    Heap-based Buffer Overflow

Sources

Status
PUBLISHED
Assigner
microsoft
Published
Updated
Nov 10, 2026, 9:32 PM
Reserved
Jul 29, 2026, 10:49 PM
Status
Modified
Published
Sep 8, 2026, 6:18 PM
Modified
Sep 17, 2026, 8:17 PM