CVE-2024-28908: OLE DB Driver for SQL Server RCE Flaw

CVE-2024-28908 Overview

CVE-2024-28908 is a remote code execution vulnerability in the Microsoft OLE DB Driver for SQL Server. The flaw is classified as a heap-based buffer overflow [CWE-122] and carries a CVSS 3.1 score of 8.8. Exploitation requires an authenticated user on a vulnerable client to connect to an attacker-controlled SQL Server instance. Successful exploitation grants the attacker code execution in the context of the connecting application.

The vulnerability affects the OLE DB Driver shipped with Microsoft SQL Server 2019 and SQL Server 2022, plus the standalone OLE DB Driver redistributable. Microsoft published the advisory on April 9, 2024.

Critical Impact
An attacker who convinces a user to connect to a malicious SQL Server can execute arbitrary code on the client, leading to data compromise, lateral movement, and full host takeover.

Affected Products

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

Discovery Timeline

2024-04-09 - CVE-2024-28908 published to the National Vulnerability Database
2024-04-09 - Microsoft releases security update via MSRC advisory
2025-01-07 - Last updated in NVD database

Technical Details for CVE-2024-28908

Vulnerability Analysis

The defect is a heap-based buffer overflow inside the Microsoft OLE DB Driver for SQL Server. The driver implements the Tabular Data Stream (TDS) protocol used by client applications to communicate with SQL Server. When the driver parses certain server-sent response structures, it allocates a heap buffer based on an attacker-influenced size field but writes data beyond the allocated boundary.

Writing past the buffer corrupts adjacent heap metadata and object pointers. An attacker who controls the response payload can shape the heap layout to redirect execution into attacker-supplied code. The vulnerability executes in the address space of the application that loaded the driver, such as a reporting tool, ETL agent, or custom line-of-business client.

The attack vector is network-based, requires no privileges on the target, but does require user interaction. A user must initiate a database connection to the malicious server, typically by opening a link, configuration file, or data source pointing to the attacker's endpoint.

Root Cause

The root cause is improper validation of length fields in server-to-client TDS messages before they are copied into a heap-allocated destination buffer. The driver trusts size metadata supplied by the remote server. A crafted oversized field causes the copy to exceed the allocated region. Microsoft has not released the specific function names or offsets affected. See the Microsoft CVE-2024-28908 Advisory for vendor technical details.

Attack Vector

The exploitation flow requires three conditions. First, an attacker stands up a rogue SQL Server endpoint that returns malformed TDS responses. Second, a victim application using a vulnerable OLE DB Driver initiates a connection to that endpoint. Third, the malformed response triggers the heap overflow during connection handshake or query processing. The attacker then achieves code execution under the privileges of the calling process.

No public proof-of-concept code is available for this vulnerability. The vulnerability mechanism is described in prose because no verified exploit samples have been released.

Detection Methods for CVE-2024-28908

Indicators of Compromise

Outbound TDS connections (TCP/1433 or custom ports) from workstations or application servers to untrusted external IP addresses or domains.
Unexpected child processes spawned by applications that host the OLE DB Driver, such as Excel.exe, SSMS.exe, or custom data integration executables.
Crashes or unhandled exceptions in processes that load msoledbsql.dll shortly after a database connection attempt.

Detection Strategies

Inventory all hosts loading msoledbsql.dll and confirm driver file versions against the patched baselines listed in the Microsoft advisory.
Inspect TDS traffic at egress points for connections to non-corporate SQL Server endpoints, and alert on connections to newly registered domains.
Hunt for process-injection or command-execution behavior originating from processes that recently established outbound SQL connections.

Monitoring Recommendations

Forward endpoint process telemetry, module-load events, and outbound network flows to a centralized analytics platform for correlation.
Establish baselines of expected SQL Server destinations per business unit and alert on deviations.
Monitor for repeated crashes of applications that consume the OLE DB Driver, which may indicate exploitation attempts or unstable exploits.

How to Mitigate CVE-2024-28908

Immediate Actions Required

Apply the April 2024 Microsoft security updates for SQL Server 2019, SQL Server 2022, and the standalone OLE DB Driver for SQL Server redistributable.
Identify every workstation, jump host, and application server that has the OLE DB Driver installed, including bundled installations from third-party software.
Restrict outbound TCP/1433 and other SQL Server ports at the perimeter to known, authorized database endpoints only.
Educate users about the risk of connecting to untrusted database connection strings, ODC files, or shared data source links.

Patch Information

Microsoft released fixed builds of the OLE DB Driver and the SQL Server client components on April 9, 2024. Refer to the Microsoft CVE-2024-28908 Advisory for the specific Knowledge Base articles and driver file versions that correspond to each supported SQL Server release. Apply patches to both server installations and any standalone driver deployments.

Workarounds

Block outbound connections to untrusted SQL Server endpoints at host firewalls and network egress filters until patches are deployed.
Remove the OLE DB Driver from hosts that do not require SQL Server connectivity.
Enforce application allow-listing so that only approved data clients can load msoledbsql.dll and initiate TDS connections.

bash

# Verify installed OLE DB Driver version on Windows
wmic datafile where name="C:\\Windows\\System32\\msoledbsql.dll" get Version

# Block outbound TDS to untrusted networks (example, adjust scope)
New-NetFirewallRule -DisplayName "Block-Outbound-TDS-Untrusted" `
  -Direction Outbound -Protocol TCP -RemotePort 1433 `
  -RemoteAddress Internet -Action Block