CVE-2025-53736 in Word
Summary
by MITRE • 08/12/2025
Buffer over-read in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 08/19/2025
Microsoft Office Word contains a buffer over-read vulnerability that occurs when processing specially crafted malicious documents. This flaw exists in the way Word handles certain data structures during document parsing operations, specifically when dealing with improperly formatted or corrupted content within word processing files. The vulnerability stems from insufficient bounds checking mechanisms that fail to validate the size of data buffers before reading from them. When a malicious document is opened, the application attempts to read beyond the allocated memory boundaries, potentially exposing sensitive data from adjacent memory locations. This type of vulnerability falls under the CWE-125 category of out-of-bounds read conditions, which represents a fundamental flaw in memory management and input validation. The security impact of this vulnerability is particularly concerning as it enables local information disclosure attacks where an attacker can potentially extract confidential data such as encryption keys, passwords, or other sensitive information stored in memory. The flaw is particularly dangerous in environments where users frequently open documents from untrusted sources, as the attack can be initiated simply by opening a malicious file. According to ATT&CK framework, this vulnerability aligns with technique T1059.001 for command and scripting interpreter and T1566 for malicious file delivery, as it represents a common attack vector through document-based malware. The vulnerability affects multiple versions of Microsoft Office Word and can be exploited through various file formats including .doc, .docx, and other document types supported by the application. The over-read condition occurs during the rendering process of document elements, particularly when handling complex formatting or embedded objects that trigger memory access violations. This type of vulnerability is classified as a local information disclosure issue because the attack requires the user to open the malicious document, making it a user-initiated attack vector rather than a remote code execution flaw. The memory corruption pattern suggests that the application does not properly validate the length of data structures before processing them, leading to unintended memory access patterns that can reveal previously stored data. Organizations should consider this vulnerability as part of their broader security posture assessment, particularly in environments where document processing is frequent and where users may encounter untrusted files. The exploitation of this vulnerability can lead to significant data exposure risks, potentially compromising sensitive business information or personal data stored within the application's memory space. Mitigation strategies should include regular security updates from Microsoft, user education regarding document safety, and implementation of additional security controls such as application whitelisting and sandboxing techniques. Security professionals should monitor for indicators of compromise related to this vulnerability and ensure that all Office installations are updated with the latest security patches to prevent exploitation attempts. The vulnerability demonstrates the ongoing need for robust input validation and memory safety practices in enterprise applications, particularly those handling untrusted data from external sources.