# CVE-2026-55121: Microsoft Office Information Disclosure Vulnerability

CVE-2026-55121 is fixed in 5 products on 1 platform, first by KB5002887, released July 14, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-55121
- Priority: Routine
- CVSS: 5.5 (Important)
- EPSS: 0.0051
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Unlikely
- Published: Jul 14, 2026
- Weakness: Out-of-bounds Read
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55121

## Description

<p>Out-of-bounds read in Microsoft Office allows an unauthorized attacker to disclose information locally.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Office 2016 (32-bit edition) |  | [KB5002887](https://patchblox.com/security/data/fix/microsoft/kb5002887.md) | Jul 14, 2026 |
| Microsoft | Microsoft Office 2016 (64-bit edition) |  | [KB5002887](https://patchblox.com/security/data/fix/microsoft/kb5002887.md) | Jul 14, 2026 |
| Microsoft | Microsoft SharePoint Enterprise Server 2016 |  | [KB5002891](https://patchblox.com/security/data/fix/microsoft/kb5002891.md) | Jul 14, 2026 |
| Microsoft | Microsoft SharePoint Enterprise Server 2016 |  | [KB5002892](https://patchblox.com/security/data/fix/microsoft/kb5002892.md) | Jul 14, 2026 |
| Microsoft | Microsoft SharePoint Server 2019 |  | [KB5002883](https://patchblox.com/security/data/fix/microsoft/kb5002883.md) | Jul 14, 2026 |
| Microsoft | Microsoft SharePoint Server 2019 |  | [KB5002885](https://patchblox.com/security/data/fix/microsoft/kb5002885.md) | Jul 14, 2026 |
| Microsoft | Microsoft SharePoint Server Subscription Edition |  | [KB5002882](https://patchblox.com/security/data/fix/microsoft/kb5002882.md) | Jul 14, 2026 |

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Data as of 2026-11-08T13:06:02Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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