Microsoft SQL Server: Heap-based buffer overflow allows remote code execution
Summary
A heap-based buffer overflow in Microsoft SQL Server allows an authorized attacker to execute code over the network. The attacker needs a valid low-privileged account, but no user interaction is required. Successful exploitation could lead to full compromise of confidentiality, integrity and availability of the database server.
Affected
- SQL Server 2017 (GDR): 14.0.0 to below 14.0.2150.2 (unverified)
- SQL Server 2017 x64 (CU31): 14.0.3006.16 to below 14.0.3570.2 (unverified)
- SQL Server 2019 (GDR): 15.0.0 to below 15.0.2210.4 (unverified)
- SQL Server 2019 x64 (CU32): 15.0.4003.23 to below 15.0.4510.2 (unverified)
- SQL Server 2022 (GDR): 16.0.0 to below 16.0.1220.3 (unverified)
- SQL Server 2022 x64 (CU27): 16.0.4003.1 to below 16.0.4315.2 (unverified)
- SQL Server 2025 CU10: 17.0.4006.0 to below 17.0.5045.3 (unverified)
- SQL Server 2025 x64 (GDR): 17.0.1050.2 to below 17.0.1155.3 (unverified)
Fixed in
- Fixed builds must be confirmed on the MSRC update guide before deployment.
- Secondary sources list SQL Server 2017 (GDR) 14.0.2150.2 and CU31 14.0.3570.2, but Microsoft's KB for the October 2026 2017 GDR release lists 14.0.2140.2. This conflict is unresolved.
- Other fixed builds: Unknown.
Workaround
Unknown.
Exploitation
- Not known to be exploited according to OffSeq; no confirmation from Microsoft or CISA KEV.
- A November 2026 Patch Tuesday roundup reports one exploited vulnerability, but it cannot be linked to this CVE.
- Public proof of concept: Unknown.
Our recommendation
- Read the MSRC entry and confirm the fixed build for each installed SQL Server branch (2017, 2019, 2022, 2025).
- Inventory all SQL Server instances and their builds, including GDR and CU versions.
- Patch in the next maintenance window, sooner if SQL Server is reachable from untrusted networks.
- Block direct internet access to SQL Server ports and limit SQL logins to the minimum required.
- Review accounts with login rights and remove unused ones.
- Plan upgrades for any SQL Server 2017 instance still in use, as mainstream support has ended.
- Recheck NVD and CISA KEV after analysis is complete.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-94511 msrc.microsoft.com
- OffSeq Radar: CVE-2026-94511 radar.offseq.com
- Microsoft KB5128497: SQL Server 2017 GDR October 2026 support.microsoft.com
- TriNetri Ops: November 2026 Patch Tuesday trinetriops.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 10 Nov 2026, 20:55.
Original description (NVD)
Heap-based buffer overflow in SQL Server allows an authorized attacker to execute code over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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