Sep 2025: Microsoft Excel Remote Code Execution Vulnerability
CVE-2025-54899 Published on September 9, 2025
Microsoft Excel Remote Code Execution Vulnerability
Free of memory not on the heap in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Weakness Type
Free of Memory not on the Heap
The application calls free() on a pointer to memory that was not allocated using associated heap allocation functions such as malloc(), calloc(), or realloc(). When free() is called on an invalid pointer, the program's memory management data structures may become corrupted. This corruption can cause the program to crash or, in some circumstances, an attacker may be able to cause free() to operate on controllable memory locations to modify critical program variables or execute code.
Products Associated with CVE-2025-54899
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Affected Versions
Microsoft 365 Apps for Enterprise:- Version 16.0.1 and below https://aka.ms/OfficeSecurityReleases is affected.
- Version 16.0.0.0 and below 16.0.5517.1000 is affected.
- Version 19.0.0 and below https://aka.ms/OfficeSecurityReleases is affected.
- Version 16.0.1 and below https://aka.ms/OfficeSecurityReleases is affected.
- Version 16.0.0 and below https://aka.ms/OfficeSecurityReleases is affected.
- Version 16.0.1 and below 16.101.25091314 is affected.
- Version 16.0.0 and below 16.101.25091314 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.