# CVE-2026-120788 — Microsoft 365 Apps for Enterprise

> As of 2026-11-11, CVE-2026-120788 is a HIGH-severity vulnerability in Microsoft 365 Apps for Enterprise, CVSS v3.1 8.8. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-120788, most recently “Microsoft Patch Tuesday November 2026: ~1,095 vulnerabilities, 64 critical, one exploited Outlook NTLM-leak spoofing zero-day (CVE-2026-124194)”.

**Last updated:** 2026-11-11

## What is CVE-2026-120788?

Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.

The record classifies CVE-2026-120788 under weakness class [CWE-122](https://intel.threadlinqs.com/cwe/CWE-122). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 7 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 1 day ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.8 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C`)
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 4.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-11-10

## Is CVE-2026-120788 being exploited?

It currently carries a trending score of 35 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Microsoft](https://intel.threadlinqs.com/vendors/microsoft): 365 Apps for Enterprise, Office 365 for Mac, Office LTSC 2021, Office LTSC 2024, Office LTSC for Mac 2021, Office LTSC for Mac 2024, Office Online Server

## How to fix CVE-2026-120788

Patch reference: [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-120788](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-120788). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2026-120788

1 tracked threat in the Threadlinqs corpus references CVE-2026-120788, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Microsoft Patch Tuesday November 2026: ~1,095 vulnerabilities, 64 critical, one exploited Outlook NTLM-leak spoofing zero-day (CVE-2026-124194)](https://intel.threadlinqs.com/threat/TL-2026-5711) — CRITICAL · 2026-11-11

## Sources

Enriched from CVE.org, NVD. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [msrc.microsoft.com — vendor advisory](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-120788)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-120788
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