# CVE-2026-85839: Microsoft WDAC OLE DB provider for SQL heap buffer overflow

Source: https://junglewise.ai/threats/cve-2026-85839-heap-based-buffer-overflow-in-microsoft-wdac-ole-db-provider-for  
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-2026-85839 · Severity: high · CVSS 8.8 · Published 2026-11-10

Microsoft's WDAC OLE DB provider for SQL contains a heap buffer overflow vulnerability that allows attackers to execute arbitrary code remotely without authentication. An attacker on a network could exploit this to gain complete control of affected systems and access sensitive SQL Server data.

Technologies: [Microsoft WDAC OLE DB provider for SQL](https://junglewise.ai/threats/technologies/wdac-ole-db-provider-for-sql). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-85839 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-85839 being exploited in the wild.

**How severe is CVE-2026-85839?** High severity, with a CVSS score of 8.8, published 10 November 2026.

**Which products and versions are affected?** Microsoft WDAC OLE DB provider for SQL.

**Is there a fix for CVE-2026-85839?** 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-2026-85839 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-85839?** Check whether you run Microsoft WDAC OLE DB provider for SQL. 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 exists in the WDAC OLE DB provider for SQL, allowing unauthenticated remote code execution via network attack vectors. The vulnerability enables an attacker to corrupt heap memory and execute arbitrary code with the privileges of the process handling the OLE DB connection.

## Affected products

- Microsoft WDAC OLE DB provider for SQL

## Timeline

- 2026-11-10: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85839](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85839)

## Related threats

- [Microsoft WDAC OLE DB provider for SQL heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-88222-heap-based-buffer-overflow-in-microsoft-wdac-ole-db-provider-for)
- [Microsoft WDAC OLE DB provider for SQL heap buffer overflow](https://junglewise.ai/threats/cve-2026-85838-heap-based-buffer-overflow-in-microsoft-wdac-ole-db-provider-for)
- [Microsoft WDAC OLE DB Provider heap buffer overflow](https://junglewise.ai/threats/cve-2026-116699-heap-based-buffer-overflow-in-microsoft-wdac-ole-db-provider-for)
- [Microsoft WDAC OLE DB provider heap buffer overflow](https://junglewise.ai/threats/cve-2026-72933-microsoft-wdac-ole-db-provider-heap-buffer-overflow)