CVE-2022-29109 in Excel
Summary
by MITRE • 05/11/2022
Microsoft Excel Remote Code Execution Vulnerability. This CVE ID is unique from CVE-2022-29110.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 05/19/2026
Microsoft Excel contains a remote code execution vulnerability that arises from improper handling of specially crafted spreadsheet files during the parsing process. The flaw exists in how Excel processes certain elements within workbook files, particularly when dealing with malformed or maliciously constructed data structures that trigger unexpected behavior in the application's internal processing mechanisms. This vulnerability specifically affects the way Excel interprets and executes code within spreadsheet objects, creating a path for remote attackers to execute arbitrary commands on affected systems. The issue stems from insufficient input validation and boundary checking within Excel's spreadsheet parsing engine, allowing attackers to craft malicious files that exploit memory corruption vulnerabilities during file processing. The vulnerability is particularly concerning because it can be triggered through normal file opening operations, requiring no special privileges or user interaction beyond opening the malicious file. This represents a critical security gap that enables attackers to gain unauthorized access to systems running vulnerable versions of Microsoft Excel.
The technical implementation of this vulnerability involves exploitation of memory management flaws within Excel's object model processing capabilities. When a malicious spreadsheet file is opened, the application's parsing routines encounter malformed data structures that cause memory corruption, leading to potential code execution in the context of the current user. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, where insufficient bounds checking allows attackers to overwrite memory locations and redirect execution flow. Attackers can leverage this weakness by constructing spreadsheet files containing specially crafted data that, when processed by Excel, triggers the memory corruption scenario. The exploitation typically involves manipulating cell data, formula structures, or object references within the spreadsheet to create conditions that lead to arbitrary code execution. This type of vulnerability falls under the ATT&CK technique T1059.005 for Command and Scripting Interpreter, as it enables execution of commands through the compromised Excel application. The flaw is particularly dangerous because it can be delivered through email attachments, file sharing platforms, or web downloads, making it a prevalent attack vector for social engineering campaigns.
The operational impact of CVE-2022-29109 extends beyond simple remote code execution to encompass complete system compromise and data exfiltration capabilities. Once successfully exploited, attackers can establish persistent access to target systems, deploy additional malware payloads, and conduct reconnaissance activities without detection. The vulnerability affects Microsoft Excel versions across multiple operating systems including Windows, macOS, and mobile platforms, creating a broad attack surface that organizations must address. Organizations relying heavily on spreadsheet processing for business operations face significant risk, as the vulnerability can be exploited through routine file handling operations, making it difficult to defend against through traditional security measures. The remote nature of the exploit means that attackers can target users from anywhere in the world without requiring physical access to the target systems. This vulnerability enables attackers to bypass many traditional security controls, as the exploitation occurs within the legitimate application context, making detection more challenging. The impact is particularly severe in enterprise environments where Excel is widely used for data analysis, financial reporting, and collaborative document sharing, as these scenarios provide multiple opportunities for successful exploitation.
Mitigation strategies for CVE-2022-29109 require immediate action including deployment of Microsoft security patches and updates to affected systems. Organizations should implement strict file validation policies that prevent opening of untrusted spreadsheet files, particularly those received through email or downloaded from unverified sources. Network segmentation and application whitelisting can help reduce the attack surface by limiting which systems can process potentially malicious files. Security teams should monitor for suspicious file opening activities and implement behavioral analysis tools to detect anomalous Excel processing patterns. Regular security awareness training for employees is essential to prevent successful social engineering attacks that leverage this vulnerability. System administrators should consider implementing additional security measures such as disabling automatic file execution, restricting Excel's ability to access external resources, and configuring secure browsing settings. The vulnerability also necessitates enhanced monitoring of system logs for evidence of exploitation attempts and implementation of automated threat detection systems. Organizations should maintain current vulnerability management processes that include regular scanning for affected systems and rapid deployment of security patches. Microsoft recommends immediate patching of all affected systems and implementation of layered security controls to reduce the risk of successful exploitation. The remediation process should include comprehensive testing of patches in controlled environments before widespread deployment to ensure compatibility with existing business applications and workflows.