Vulnerability · Published Aug 11, 2026 · Assigned by microsoft
CVE-2026-70329Microsoft Outlook Remote Code Execution Vulnerability
High 8.8
In plain English
A high-severity integer overflow in Microsoft 365 Apps for Enterprise from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 57% of all known vulnerabilities).
Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.8%top 42.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Integer overflow or wraparound in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft 365 Apps for Enterprise | 16.0.1 – before https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Office 2019 | 19.0.0 – before https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Office LTSC 2021 | 16.0.1 – before https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Office LTSC 2024 | 16.0.0 – before https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Outlook 2016 | 16.0.0.0 – before 16.0.5565.1000 |
Weakness: CWE-190 · Vector: 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
References
- Microsoft Outlook Remote Code Execution Vulnerability vendor-advisory, patch