CVE-2020-1332 in Office
Summary
by MITRE
<p>A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.</p> <p>Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Excel. In an email attack scenario, an attacker could exploit the vulnerability by sending the specially crafted file to the user and convincing the user to open the file. In a web-based attack scenario, an attacker could host a website (or leverage a compromised website that accepts or hosts user-provided content) containing a specially crafted file designed to exploit the vulnerability. An attacker would have no way to force users to visit the website. Instead, an attacker would have to convince users to click a link, typically by way of an enticement in an email or instant message, and then convince them to open the specially crafted file.</p> <p>The security update addresses the vulnerability by correcting how Microsoft Excel handles objects in memory.</p>
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 02/24/2026
The vulnerability identified as CVE-2020-1332 represents a critical remote code execution flaw within Microsoft Excel software that stems from improper handling of memory objects. This weakness falls under the category of memory corruption vulnerabilities and aligns with CWE-125, which describes out-of-bounds read conditions that can lead to arbitrary code execution. The flaw exists in the way Excel processes specially crafted file formats that contain malformed objects in memory, creating opportunities for attackers to inject and execute malicious code within the context of the currently logged-on user. The vulnerability is particularly dangerous because it can be exploited through multiple attack vectors, including email attachments and web-based delivery methods, making it a significant concern for enterprise security environments.
The exploitation of this vulnerability requires user interaction, specifically the opening of a maliciously crafted Excel file, which demonstrates the social engineering component necessary for successful exploitation. According to the ATT&CK framework, this represents a technique categorized under T1204.002 - User Execution: Malicious File, where attackers rely on users to execute malicious payloads. The attack scenario typically involves an attacker crafting a specially designed Excel file that contains memory corruption elements designed to trigger the vulnerability when opened. This approach leverages the trust users place in common file formats and the expectation that office applications will handle documents safely. The exploitation process requires the attacker to carefully construct memory objects that will cause Excel to behave unpredictably, leading to code execution in the user's security context.
The operational impact of CVE-2020-1332 extends beyond simple code execution, as successful exploitation can result in complete system compromise when users operate with administrative privileges. This vulnerability can be leveraged to install programs, modify or delete data, and create new accounts with full user rights, effectively granting attackers persistent access to the compromised system. The risk assessment indicates that users with administrative rights face the most severe consequences, as they can bypass system protections and establish backdoors for continued access. Organizations must consider that this vulnerability can be exploited through various delivery mechanisms, including phishing emails that contain malicious Excel files or compromised websites that host exploit code. The attack surface is broad because Excel is widely used across enterprise environments and is often opened without sufficient security awareness training.
Microsoft's security update for this vulnerability addresses the root cause by implementing proper memory handling procedures within Excel's object processing mechanisms. The fix involves modifying how Excel parses and validates objects in memory, ensuring that malformed or maliciously constructed elements are properly sanitized before execution. Security professionals should note that this vulnerability demonstrates the importance of maintaining up-to-date software patches and the potential for seemingly benign file formats to serve as attack vectors. Organizations should implement layered security approaches including email filtering, web application firewalls, and user education programs to reduce the risk of exploitation. The vulnerability also highlights the necessity of application whitelisting and privileged access management controls to limit the potential impact of successful exploitation, particularly in environments where administrative privileges are commonly used by end users.