# CVE-2019-1109: Microsoft Office Spoofing Vulnerability

CVE-2019-1109 is fixed in 5 products on 1 platform, first by KB4018375, released July 9, 2019. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2019-1109
- Priority: High
- CVSS: n/a (Important)
- EPSS: 0.0424
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Jul 9, 2019
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1109

## Description

<p>A spoofing vulnerability exists when Microsoft Office Javascript does not check the validity of the web page making a request to Office documents.</p> <p>An attacker who successfully exploited this vulnerability could read or write information in Office documents.</p> <p>The security update addresses the vulnerability by correcting the way that Microsoft Office Javascript verifies trusted web pages.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Office 2013 RT Service Pack 1 |  | [KB4018375](https://patchblox.com/security/data/fix/microsoft/kb4018375.md) | Jul 9, 2019 |
| Microsoft | Microsoft Office 2013 Service Pack 1 (32-bit editions) |  | [KB4018375](https://patchblox.com/security/data/fix/microsoft/kb4018375.md) | Jul 9, 2019 |
| Microsoft | Microsoft Office 2013 Service Pack 1 (64-bit editions) |  | [KB4018375](https://patchblox.com/security/data/fix/microsoft/kb4018375.md) | Jul 9, 2019 |
| Microsoft | Microsoft Office 2016 (32-bit edition) |  | [KB4464534](https://patchblox.com/security/data/fix/microsoft/kb4464534.md) | Jul 9, 2019 |
| Microsoft | Microsoft Office 2016 (64-bit edition) |  | [KB4464534](https://patchblox.com/security/data/fix/microsoft/kb4464534.md) | Jul 9, 2019 |

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Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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