# CVE-2026-67646: Microsoft SQL Server heap buffer overflow

Source: https://junglewise.ai/threats/cve-2026-67646-heap-based-buffer-overflow-in-sql-server-allows-an-authorized  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-10. Updated: 2026-11-10  
License: CC BY 4.0 with a link back

CVE-2026-67646 · Severity: high · CVSS 8.8 · Published 2026-11-10

Microsoft SQL Server contains a heap-based buffer overflow vulnerability that allows an authorized network user to execute arbitrary code with SQL Server privileges. An attacker with valid database credentials could exploit this to gain full control of the database server and potentially the underlying system, leading to data theft, corruption, or service disruption.

Technologies: [Microsoft SQL Server](https://junglewise.ai/threats/technologies/sql-server). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-67646 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-67646 being exploited in the wild.

**How severe is CVE-2026-67646?** High severity, with a CVSS score of 8.8, published 10 November 2026.

**Which products and versions are affected?** Microsoft SQL Server.

**Is there a fix for CVE-2026-67646?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-67646 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-67646?** Check whether you run Microsoft SQL Server. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A heap-based buffer overflow in SQL Server allows an authenticated attacker to execute arbitrary code over the network without requiring user interaction. The vulnerability requires valid database credentials to trigger, but once exploited grants complete code execution at the SQL Server process level. No public exploit has been reported in the wild.

## Affected products

- Microsoft SQL Server

## Timeline

- 2026-11-10: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-67646](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-67646)

## Related threats

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- [Microsoft SQL Server heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-94511-heap-based-buffer-overflow-in-sql-server-allows-an-authorized)
- [Microsoft SQL Server heap buffer overflow](https://junglewise.ai/threats/cve-2026-88111-heap-based-buffer-overflow-in-sql-server-allows-an-authorized)
- [Microsoft SQL Server privilege escalation via exposed method](https://junglewise.ai/threats/cve-2026-84010-exposed-dangerous-method-or-function-in-sql-server-allows-an)
- [Microsoft SQL Server information disclosure via uninitialized resource](https://junglewise.ai/threats/cve-2026-68783-use-of-uninitialized-resource-in-sql-server-allows-an-authorized)