Microsoft Office Excel: Remote code execution via untrusted pointer dereference
Summary
Microsoft Excel, part of Microsoft 365 Apps and Office, contains an untrusted pointer dereference that allows remote code execution. An unauthorized attacker can run code over the network if a user opens a crafted file, most likely a phishing attachment or a shared workbook. The CVSS score is 8.8 (high), with high impact on confidentiality, integrity and availability, and the code runs with the rights of the user.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 before the Office security release (exact build not given in the CVE record)
- Office 365 for Mac: 1.0.0 before 16.115.26110837
- Office LTSC 2021: 16.0.1 before 16.0.14334.21048
- Office LTSC for Mac 2021: 16.0.1 before 16.115.26110837
- Office LTSC 2024: 16.0.0 before 16.0.17932.21140 (from third-party mirrors, to be confirmed on MSRC)
- Office LTSC for Mac 2024: 16.0.0 before 16.115.26110837 (from third-party mirrors, to be confirmed on MSRC)
- Office Online Server: 16.0.0.0 before 16.0.10417.20236 (from third-party mirrors, to be confirmed on MSRC)
Fixed in
- Fixed builds are listed on the Microsoft Security Update Guide (MSRC) advisory for CVE-2026-118724.
- Microsoft 365 Apps and Office LTSC: expected to be fixed in the November 2026 security update; not confirmed from a primary source.
- Microsoft 365 Apps for Enterprise: specific fixed build unknown.
Workaround
- Unknown. No vendor-published workaround was found.
- Until patched, keep Protected View and Mark-of-the-Web enabled, block or quarantine macro-enabled and unsolicited spreadsheet attachments at the mail gateway, and do not open Office files from untrusted sources.
Exploitation
- Exploited in the wild: No evidence found; no KEV entry.
- Public proof of concept: Unknown.
- Microsoft exploitability assessment: Not found.
- CISA SSVC: Exploitation none, automatable no, technical impact total.
Our recommendation
- Apply the November 2026 Office and Microsoft 365 updates on the same day, and verify the update channels work on all clients.
- Confirm the fixed build numbers and exploitability on the MSRC advisory before closing the ticket.
- Restrict opening files from unknown senders and enforce mail filtering for spreadsheet attachments.
- Monitor for NVD analysis, KEV addition and public proof-of-concept reports, and patch promptly if exploitation is reported.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Remote code execution – Microsoft Office Excel
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Microsoft Office
- Updates (KB)
- KB5002946
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-118724 msrc.microsoft.com
- CVE Record: CVE-2026-118724 www.cve.org
- Strix: CVE-2026-118724 www.strix.ai
- threatint: CVE-2026-118724 cve.threatint.com
- Cybersecurity News: Microsoft November 2026 Patch Tuesday cybersecuritynews.com
- Trinetri Ops: Patch Tuesday November 2026 trinetriops.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, 21:44.
Original description (NVD)
Untrusted pointer dereference in Microsoft Office Excel 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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