Overview
CVE-2025-53759 is a serious vulnerability that affects Microsoft Office Excel, a widely-used spreadsheet software. This flaw allows unauthorized attackers to execute code locally on the victim’s system, leading to potential system compromise or data leakage. Given the widespread use of Excel in organizations across various sectors, this vulnerability poses a significant risk. Its successful exploitation could result in severe business disruption or even financial loss.
Vulnerability Summary
CVE ID: CVE-2025-53759
Severity: High (7.8 CVSS Score)
Attack Vector: Local
Privileges Required: None
User Interaction: Required
Impact: Unauthorized code execution, potential system compromise, or data leakage
Affected Products
Share secrets securely
Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.
Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.
- • Encrypted identity
- • Private Spaces for organizations and teams
- • End-to-end encrypted chat, calls, files, and notes
- • Sensitive AI work and protected collaboration
- • Built for information that cannot leak
Our mission is to secure human work alongside AI.
Product | Affected Versions
Microsoft Office Excel | All versions before the patch
How the Exploit Works
The exploit works by taking advantage of an uninitialized resource within Microsoft Office Excel. An attacker crafts a malicious Excel file containing specially designed code. Once the victim opens this file, the code is executed locally on the victim’s machine due to the software’s failure to properly initialize a resource. This allows the attacker to execute arbitrary code or commands in the context of the current user. If the user holds administrative rights, the attacker could take control of the affected system.
Conceptual Example Code
Below is a conceptual example of how an attacker might craft a malicious payload within an Excel file:
Sub Workbook_Open()
Shell("cmd.exe /c [malicious_command]", vbHide)
End SubIn this example, the `Workbook_Open` subroutine runs when the Excel file is opened, executing the malicious command in the Windows command line via the `Shell` function.
Mitigation Guidance
Users are strongly recommended to immediately apply the vendor patch provided by Microsoft to remediate this vulnerability. As a temporary mitigation, users can also employ a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to detect and potentially block attempts to exploit this vulnerability. However, these measures should not replace the need to apply the vendor patch, which provides a complete fix.