Microsoft Office OneNote: Remote code execution via command injection
Summary
A command injection flaw (CWE-77) in Microsoft Office OneNote, part of Microsoft 365 Apps for Enterprise, allows an unauthenticated remote attacker to execute code. The attack requires that a user opens a specially crafted OneNote link sent by the attacker. The CVSS base score is 8.8 (High), with high impact on confidentiality, integrity and availability.
Affected
- Microsoft 365 Apps for Enterprise, version 16.0.1 and later (per CNA record; the exact affected range is given by a link in the record)
- Office LTSC 2021: unclear, not listed in the CNA data; verify before assuming it is affected
Fixed in
- Unknown. The fixed build number was not confirmed in the sources reviewed. Check the MSRC advisory for the Security Update and KB links.
Workaround
- No workaround is documented by the vendor in the sources reviewed.
- Until patched, be cautious with unexpected OneNote links received by email or chat (own recommendation, not vendor guidance).
Exploitation
- Microsoft's temporal vector marks exploitation as unproven (E:U).
- No in-the-wild exploitation or public proof of concept was found in the sources reviewed.
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
Our recommendation
- Patch Microsoft 365 Apps for Enterprise promptly once the fixed build is confirmed on the MSRC page.
- Prioritise users who regularly handle external links and documents.
- Check for Office LTSC 2021 installations and plan their replacement or review, as no fix may be provided.
- Train users to treat unexpected OneNote links with caution.
- Verify the NVD status and published date against NVD and MSRC, as secondary aggregators showed differing data.
Information from Microsoft (Patch Tuesday October 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-97781 msrc.microsoft.com
- Microsoft Learn: Office security updates learn.microsoft.com
- Qualys: Microsoft Patch Tuesday October 2026 review blog.qualys.com
- Office Watch: October 2026 Patch Tuesday Office critical fixes office-watch.com
- Vulners: CVE-2026-97781 vulners.com
- threatint: CVE-2026-97781 cve.threatint.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 31 Oct 2026, 17:17.
Original description (NVD)
Improper neutralization of special elements used in a command ('command injection') in Microsoft Office OneNote 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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