# CVE-2026-70329 — Microsoft 365 Apps for Enterprise

> As of 2026-08-12, CVE-2026-70329 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-2026-70329, most recently “CVE-2026-70329: Microsoft Outlook Remote Code Execution via Integer Overflow”.

**Last updated:** 2026-08-12

## What is CVE-2026-70329?

Integer overflow or wraparound in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.

The record classifies CVE-2026-70329 under weakness class [CWE-190](https://intel.threadlinqs.com/cwe/CWE-190). 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. 5 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 55 days 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:** 2026-08-11, last modified 2026-08-12

## Is CVE-2026-70329 being exploited?

No public exploitation evidence for CVE-2026-70329 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-08-12. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.

## Affected products and versions

- [Microsoft](https://intel.threadlinqs.com/vendors/microsoft): 365 Apps for Enterprise, Office 2019, Office LTSC 2021, Office LTSC 2024, Outlook 2016

## How to fix CVE-2026-70329

No vendor patch reference has been recorded for CVE-2026-70329 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-2026-70329

1 tracked threat in the Threadlinqs corpus references CVE-2026-70329, either in the campaign’s CVE list or as an indicator on the campaign record.

- [CVE-2026-70329: Microsoft Outlook Remote Code Execution via Integer Overflow](https://intel.threadlinqs.com/threat/TL-2026-1991) — HIGH · 2026-08-11

## Sources

Enriched from CVE.org, NVD, GitHub Security Advisories. Last verified by Threadlinqs on 2026-08-12. 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-2026-70329)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-70329
Full detection coverage and IOCs for threats exploiting CVE-2026-70329 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp