CVE-2024-21349 Overview
CVE-2024-21349 is a remote code execution vulnerability affecting Microsoft ActiveX Data Objects (ADO) across supported versions of Windows and Windows Server. The flaw is associated with CWE-122 (Heap-based Buffer Overflow) and allows an attacker to execute arbitrary code on a target system after the victim interacts with crafted content. Exploitation requires user interaction but no prior authentication. Microsoft addressed the issue in its February 2024 security updates.
Critical Impact
Successful exploitation grants attackers the ability to execute arbitrary code with the privileges of the targeted user, leading to full compromise of confidentiality, integrity, and availability.
Affected Products
- Microsoft Windows 10 (1507, 1607, 1809, 21H2, 22H2)
- Microsoft Windows 11 (21H2, 22H2, 23H2)
- Microsoft Windows Server 2008, 2012, 2016, 2019, 2022, and 2022 23H2
Discovery Timeline
- 2024-02-13 - CVE-2024-21349 published to the National Vulnerability Database (NVD)
- 2024-11-21 - Last updated in NVD database
Technical Details for CVE-2024-21349
Vulnerability Analysis
The vulnerability exists in Microsoft ActiveX Data Objects, a Component Object Model (COM) library used by Windows applications to access data sources. The flaw is classified as a heap-based buffer overflow under CWE-122. An attacker who tricks a user into opening crafted content that invokes the vulnerable ADO components can corrupt heap memory and divert execution flow. The attack vector is network-based, and successful exploitation produces high impact across confidentiality, integrity, and availability.
Root Cause
The root cause is improper validation of input sizes when ADO processes data structures on the heap. A malformed input causes the component to write outside the bounds of an allocated heap buffer. This memory corruption can be shaped to overwrite adjacent control data, enabling code execution in the context of the calling process.
Attack Vector
Exploitation requires user interaction. A typical attack chain involves delivering a crafted document, web page, or application file that loads the vulnerable ADO components when opened. Because ADO is widely embedded in Microsoft Office, scripting hosts, and line-of-business applications, the attack surface is broad. No authentication is required, and the attack can be initiated remotely over the network.
No public proof-of-concept code has been verified for this CVE. Refer to the Microsoft Security Update Guide for CVE-2024-21349 for vendor-provided technical context.
Detection Methods for CVE-2024-21349
Indicators of Compromise
- Unexpected child processes spawned from Microsoft Office applications, wscript.exe, or cscript.exe after a user opens external content
- Crash events or Windows Error Reporting entries referencing msado15.dll, msadox.dll, or other ADO components
- Outbound network connections from Office or scripting hosts to unfamiliar domains shortly after document open events
Detection Strategies
- Monitor process lineage where ADO-consuming applications launch shells, PowerShell, or LOLBins such as rundll32.exe and regsvr32.exe
- Inspect inbound email attachments and downloaded files for embedded OLE objects or scripts that instantiate ADODB.Connection or ADODB.Recordset
- Hunt for anomalous COM object instantiation patterns in Endpoint Detection and Response (EDR) telemetry
Monitoring Recommendations
- Enable Microsoft Defender Attack Surface Reduction rules that block Office applications from creating child processes
- Forward Windows Sysmon Event IDs 1, 7, and 11 to a centralized SIEM for correlation
- Track patch deployment status across all Windows 10, Windows 11, and Windows Server endpoints to identify unpatched systems
How to Mitigate CVE-2024-21349
Immediate Actions Required
- Apply the February 2024 Microsoft security updates to all affected Windows and Windows Server systems
- Prioritize internet-facing servers, workstations used for email and document handling, and shared infrastructure
- Validate patch deployment using vulnerability management tooling and Windows Update logs
Patch Information
Microsoft released fixes for CVE-2024-21349 as part of its February 2024 Patch Tuesday cycle. Patch details and update package identifiers for each affected Windows version are available in the Microsoft Security Update Guide.
Workarounds
- Restrict user permissions so that users do not operate with administrator privileges, limiting the impact of code execution
- Block or warn on inbound email attachments containing macros or OLE objects from external senders
- Enforce Protected View and Mark of the Web on documents originating from untrusted sources
- Disable unnecessary scripting hosts and legacy COM features on systems that do not require them
# Verify installed updates on Windows for CVE-2024-21349 remediation
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Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
