CVE-2024-28909: OLE DB Driver for SQL Server RCE Flaw

CVE-2024-28909 Overview

CVE-2024-28909 is a remote code execution vulnerability in the Microsoft OLE DB Driver for SQL Server. The flaw is classified under [CWE-122] as a heap-based buffer overflow. Microsoft published the advisory on April 9, 2024, addressing the issue across the OLE DB Driver, SQL Server 2019, and SQL Server 2022 (x64).

Exploitation requires a user to connect a vulnerable client to an attacker-controlled SQL Server. A successful attack delivers code execution in the context of the connecting application. The CVSS vector indicates network-based exploitation with user interaction and high impact across confidentiality, integrity, and availability.

Critical Impact
An attacker operating a malicious SQL Server can execute arbitrary code on any client that connects using a vulnerable OLE DB Driver, compromising data and application integrity.

Affected Products

Microsoft OLE DB Driver for SQL Server
Microsoft SQL Server 2019 (x64)
Microsoft SQL Server 2022 (x64)

Discovery Timeline

2024-04-09 - CVE-2024-28909 published to NVD by Microsoft
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-28909

Vulnerability Analysis

The vulnerability is a heap-based buffer overflow in the Microsoft OLE DB Driver for SQL Server. The driver mishandles data returned from a remote SQL Server during connection or query processing. An attacker who controls a malicious server can craft response packets that trigger the overflow on the client side.

The defect resides in the client-side parsing logic, not the SQL Server engine itself. This means any application that loads the affected OLE DB Driver — including SQL Server installations that ship it — is exposed when initiating an outbound connection. The vulnerability allows the attacker to corrupt heap memory and divert execution into attacker-controlled code.

Root Cause

The root cause is improper validation of length or size fields when the driver allocates and copies data into heap buffers. When the server returns malformed Tabular Data Stream (TDS) structures, the driver writes past the allocated boundary. This memory corruption can be shaped into a controllable write primitive leading to arbitrary code execution.

Attack Vector

The attack is network-based but requires user interaction: a victim must initiate a database connection to an attacker-controlled endpoint. Common scenarios include phishing a developer with a malicious connection string, hosting a rogue SQL Server on an internal network, or compromising DNS to redirect legitimate clients. Once a connection occurs, the malicious server returns crafted TDS responses that overflow the driver's heap buffers.

No verified public exploit code is available for CVE-2024-28909. Refer to the Microsoft Security Update CVE-2024-28909 advisory for vendor technical details.

Detection Methods for CVE-2024-28909

Indicators of Compromise

Unexpected crashes or access violations in processes loading msoledbsql.dll or sqlncli.dll.
Outbound TDS connections (TCP/1433 by default) from workstations or servers to untrusted external hosts.
Child processes spawned by applications hosting the OLE DB Driver, such as Excel, SSMS, or custom .NET hosts initiating cmd.exe or powershell.exe.

Detection Strategies

Hunt for processes loading the OLE DB Driver module that subsequently allocate executable memory or launch shell utilities.
Inspect EDR telemetry for heap corruption signals (crash dumps with HEAP_CORRUPTION or STATUS_HEAP_CORRUPTION codes) tied to SQL client applications.
Correlate authentication failures from SQL clients with outbound connections to non-corporate IP ranges.

Monitoring Recommendations

Log and review all outbound TDS traffic at the network perimeter, alerting on connections to IPs outside the database asset inventory.
Track installed versions of msoledbsql.dll across endpoints to identify unpatched hosts.
Monitor SQL Server hosts for unexpected outbound connections, since SQL Server installations also bundle the affected driver.

How to Mitigate CVE-2024-28909

Immediate Actions Required

Apply the Microsoft security update for CVE-2024-28909 to all systems running the OLE DB Driver, SQL Server 2019, and SQL Server 2022.
Inventory applications that statically or dynamically load msoledbsql.dll and prioritize them for patching.
Restrict outbound TCP/1433 and other TDS ports from user workstations to only sanctioned database servers.

Patch Information

Microsoft released a security update addressing CVE-2024-28909 on April 9, 2024. The update replaces the vulnerable OLE DB Driver binary across standalone installations and the versions bundled with SQL Server 2019 and SQL Server 2022. Refer to the Microsoft Security Update CVE-2024-28909 advisory for the correct package per platform.

Workarounds

Block egress to untrusted SQL Server endpoints using host-based or perimeter firewall rules until patching is complete.
Enforce strict validation of database connection strings in application configuration and prohibit user-supplied server names.
Train developers and analysts to avoid connecting tools such as SSMS, Excel, or Power BI to untrusted SQL Server instances.

bash

# Windows firewall example: block outbound TDS to all but approved DB servers
New-NetFirewallRule -DisplayName "Block-Outbound-TDS" -Direction Outbound `
  -Protocol TCP -RemotePort 1433 -Action Block

New-NetFirewallRule -DisplayName "Allow-Outbound-TDS-Approved" -Direction Outbound `
  -Protocol TCP -RemotePort 1433 -RemoteAddress 10.20.30.0/24 -Action Allow