Microsoft Office Word: Remote code execution via heap-based buffer overflow
Summary
Microsoft Office Word contains a heap-based buffer overflow that allows an unauthorized attacker to execute code over the network. Exploitation requires that a user opens a crafted document, for example one received by email or downloaded from the internet. The CNA rates the flaw as High (CVSS 3.1 8.8), and the CISA SSVC assessment reports no known exploitation. NVD analysis is still pending.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 up to the fixed build (the CNA record links to an aka.ms page instead of a version number)
- Office 365 for Mac: before 16.115.26110837
- Office LTSC 2021: before 16.0.14334.21048
- Office LTSC 2024 and Office LTSC for Mac 2021/2024: fixed builds unverified (a third-party source lists 16.0.17932.21140 for LTSC 2024)
Fixed in
- Install the Office security updates from November 2026 on all affected installations.
- Verify the exact fixed build numbers on the MSRC Security Update Guide.
Workaround
Unknown. No vendor workaround found; patching is the only confirmed remediation.
Exploitation
- Not known to be exploited in the wild.
- The CNA vector includes E:U (exploit code maturity Unproven).
- No public proof of concept or CISA KEV entry found at the time of research.
Our recommendation
- Apply the November 2026 Office security updates on all workstations, starting with staff who handle external documents.
- Keep Protected View enabled for files from the internet and for email attachments.
- Check installed Office build numbers against the MSRC advisory.
- Monitor for exploitation reports and a CISA KEV listing.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MSRC Security Update Guide: CVE-2026-110062 msrc.microsoft.com
- CVE Record: CVE-2026-110062 www.cve.org
- Strix: CVE-2026-110062 (third-party, unverified fixed builds) www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 10 Nov 2026, 23:42.
Original description (NVD)
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
Affected? We can help.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.