Microsoft Office Word: Remote code execution via heap-based buffer overflow
Summary
A heap-based buffer overflow (CWE-122) in Microsoft Office Word allows an unauthorized attacker to execute code over the network. The victim must open a crafted file, which is typically delivered by email or download. The CVSS base score is 8.8, with high impact on confidentiality, integrity and availability. NVD had not yet completed its analysis at publication, and the affected versions are not yet independently verified.
Affected
- Microsoft 365 Apps for Enterprise: from 16.0.1, upper bound not stated in the CVE record
- Microsoft Office 365 for Mac: before 16.115.26110837
- Microsoft Office LTSC 2021: before 16.0.14334.21048
- Microsoft Office LTSC 2024: before 16.0.17932.21140
- Microsoft Office LTSC for Mac 2021: before 16.115.26110837
- Microsoft Office LTSC for Mac 2024: before 16.115.26110837
Fixed in
- Office 365 for Mac and LTSC for Mac 2021/2024: 16.115.26110837
- Office LTSC 2021: 16.0.14334.21048
- Office LTSC 2024: 16.0.17932.21140
- Microsoft 365 Apps for Enterprise: Unknown. Check the Microsoft Office release notes.
Workaround
Unknown. No vendor workaround was found. Check the MSRC page for any listed mitigation.
Exploitation
- Exploited in the wild: Unknown. No source reports exploitation.
- Public proof of concept: Unknown.
- CISA SSVC assessment: exploitation none, not automatable, total technical impact.
Our recommendation
- Verify the CVE ID and the affected builds on the MSRC advisory before acting.
- Install the current Microsoft Office security update on all systems.
- Keep Protected View enabled and restrict macros and files from untrusted senders.
- Disable the Word preview pane and email preview where they are not needed.
- Monitor CISA KEV and the MSRC exploitation flag for changes.
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-2026-112723 msrc.microsoft.com
- Strix: CVE-2026-112723 (third-party, unverified) www.strix.ai
- Zero Day Initiative: November 2026 security update review www.zerodayinitiative.com
- Qualys: Microsoft Patch Tuesday November 2026 review blog.qualys.com
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, 23:02.
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.
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