# CVE-2026-55132 — Microsoft 365 Apps for Enterprise

> As of 2026-10-08, CVE-2026-55132 is a HIGH-severity vulnerability in Microsoft 365 Apps for Enterprise, CVSS v3.1 7.8, EPSS 0.5% (45.5th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-55132, most recently “Microsoft July 2026 Patch Tuesday: 570 Flaws Fixed, 3 Zero-Days Including AD FS and SharePoint Privilege Escalation”.

**Last updated:** 2026-10-08

## What is CVE-2026-55132?

Double free in Microsoft Office Word allows an unauthorized attacker to execute code locally.

The record classifies CVE-2026-55132 under weakness class [CWE-415](https://intel.threadlinqs.com/cwe/CWE-415). Its CVSS v3 base vector states that the flaw requires local access to the host, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 11 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 106 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.8 — HIGH (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C`)
- **EPSS (FIRST):** 0.5% probability of exploitation in the next 30 days, higher than 45.5% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-07-14, last modified 2026-10-08

## Is CVE-2026-55132 being exploited?

It currently carries a trending score of 24 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Microsoft](https://intel.threadlinqs.com/vendors/microsoft): 365 Apps for Enterprise, Office 2019, Office 365 for Mac, Office LTSC 2021, Office LTSC 2024, Office LTSC for Mac 2021, Office LTSC for Mac 2024, SharePoint Enterprise Server 2016, SharePoint Server 2019, SharePoint Server Subscription Edition, Word 2016

## How to fix CVE-2026-55132

No vendor patch reference has been recorded for CVE-2026-55132 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-55132

1 tracked threat in the Threadlinqs corpus references CVE-2026-55132, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Microsoft July 2026 Patch Tuesday: 570 Flaws Fixed, 3 Zero-Days Including AD FS and SharePoint Privilege Escalation](https://intel.threadlinqs.com/threat/TL-2026-1324) — CRITICAL · 2026-07-14

## Sources

Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-10-10.

**Vendor advisory and patch**

- [msrc.microsoft.com — vendor advisory](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55132)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-55132
Full detection coverage and IOCs for threats exploiting CVE-2026-55132 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp