CVE-2023-21741 in Visio
Summary
by MITRE • 01/11/2023
Microsoft Office Visio Information Disclosure Vulnerability.
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Analysis
by VulDB Data Team • 09/22/2025
The CVE-2023-21741 vulnerability represents a critical information disclosure flaw within Microsoft Office Visio software that allows attackers to potentially access sensitive data through malformed file structures. This vulnerability specifically affects Visio versions that process certain file formats, creating opportunities for adversaries to exploit the application's handling of structured data. The flaw manifests when Visio attempts to parse and render maliciously crafted Visio files, potentially exposing internal memory contents or system information to unauthorized parties. Such vulnerabilities are particularly concerning in enterprise environments where Visio is commonly used for diagramming and technical documentation, as they could enable attackers to gain insights into organizational infrastructure or proprietary designs.
The technical root cause of this vulnerability stems from insufficient input validation within Visio's file processing engine, which fails to properly sanitize or validate the structure of incoming Visio files. When processing specially crafted Visio documents, the application does not adequately check for malformed data or unexpected file structures that could trigger memory corruption or information leakage. This weakness aligns with CWE-20, which describes improper input validation, and represents a classic example of how inadequate sanitization of user-supplied data can lead to information disclosure vulnerabilities. The vulnerability typically occurs during the rendering or parsing phase of file processing, where Visio's internal mechanisms attempt to interpret and display complex graphical elements from the file structure. Attackers can leverage this flaw by crafting Visio files that contain malicious data patterns designed to trigger the vulnerable code paths within the application's processing pipeline.
The operational impact of CVE-2023-21741 extends beyond simple data exposure, as it can potentially enable more sophisticated attacks when combined with other exploitation techniques. Organizations using Visio for business-critical diagramming and design work face significant risk, as attackers could potentially extract sensitive information from Visio documents that contain proprietary designs, architectural blueprints, or confidential business data. The vulnerability could also serve as a stepping stone for additional attacks, particularly in environments where Visio files are shared across departments or with external partners. Given the widespread use of Microsoft Office products, this vulnerability affects numerous enterprise environments and could be exploited through various attack vectors including email attachments, document sharing platforms, or compromised websites hosting malicious Visio files. The information disclosure could potentially reveal system configurations, internal network structures, or other sensitive metadata that would be valuable to threat actors conducting reconnaissance activities.
Mitigation strategies for CVE-2023-21741 should prioritize immediate patch deployment from Microsoft, as the vendor has released security updates addressing this specific vulnerability. Organizations should implement comprehensive monitoring of Visio file processing activities and establish strict file validation policies for all incoming Visio documents. Network segmentation and access controls should be reinforced to limit potential lateral movement if an attacker successfully exploits this vulnerability. Security teams should also consider implementing email filtering rules that block suspicious Visio file attachments and establish secure document handling procedures that require manual verification before opening potentially risky files. Additionally, the implementation of application whitelisting solutions can help prevent unauthorized Visio versions from executing on critical systems. The vulnerability's exploitation risk places it within the ATT&CK framework under the T1059.001 technique for command and scripting interpreter, as attackers may use information disclosed through this vulnerability to craft more targeted attacks against the compromised environment. Organizations should also conduct regular security assessments to identify any potential exploitation attempts and maintain updated threat intelligence feeds to monitor for related attack patterns or indicators of compromise.