CVE-2026-64903
Analyzed
Analyzed - Analysis Complete
Integer Overflow in Microsoft Office Enables Local Code Execution
Vulnerability report for CVE-2026-64903, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-11
Last updated on: 2026-08-13
Assigner: Microsoft Corporation
Description
Description
Integer overflow or wraparound in Microsoft Office allows an unauthorized attacker to execute code locally.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| microsoft | 365_apps | * |
| microsoft | 365_apps | * |
| microsoft | office_2019 | * |
| microsoft | office_2019 | * |
| microsoft | office_2016 | * |
| microsoft | office_2016 | * |
| microsoft | microsoft_365 | * |
| microsoft | office_2021 | * |
| microsoft | office_2021 | * |
| microsoft | office_2021 | * |
| microsoft | office_2024 | * |
| microsoft | office_2024 | * |
| microsoft | office_2024 | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-122 | A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). |
| CWE-190 | The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number. |
