Microsoft Office Excel: Out-of-bounds read leads to elevation of privilege
Summary
An out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to elevate privileges over a network, as stated in the CVE record (CWE-125). The CVSS vector requires no privileges but user interaction, for example opening a crafted spreadsheet received by email or downloaded from the internet. Microsoft rates the impact as high for confidentiality, integrity and availability. No exploitation or public proof of concept was found as of 10 November 2026.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 before the fixed build (see MSRC)
- Office for Mac 365: 1.0.0 before 16.115.26110837
- Office LTSC 2021: 16.0.1 before 16.0.14334.21048
- Office LTSC 2024: 16.0.0 before 16.0.17932.21140 (unverified, according to aggregator)
- Office LTSC for Mac 2021 and 2024: before 16.115.26110837 (unverified, according to aggregator)
- Office Online Server: 16.0.0.0 before 16.0.10417.20236 (unverified, according to aggregator)
Fixed in
- Microsoft 365 Apps for Enterprise: Unknown. Check the MSRC advisory.
- Office for Mac 365: 16.115.26110837
- Office LTSC 2021: 16.0.14334.21048
- Office LTSC 2024: 16.0.17932.21140 (to be verified)
- Office LTSC for Mac 2021 and 2024: 16.115.26110837 (to be verified)
- Office Online Server: 16.0.10417.20236 (to be verified)
Workaround
Unknown. No workaround is documented in the sources reviewed. Check the MSRC FAQ for any mitigation.
Exploitation
- No evidence of in-the-wild exploitation found.
- Not listed in CISA KEV as of 10 November 2026.
- No public proof of concept found.
- CVSS exploit maturity is rated as unproven (E:U).
Our recommendation
- Update Microsoft 365 Apps, Office LTSC and Office for Mac clients to the builds in the MSRC advisory, starting with users who open external files.
- Verify the fixed build numbers in the MSRC advisory before rollout.
- Patch the related Excel CVEs CVE-2026-118726 and CVE-2026-118724 in the same cycle.
- Monitor for KEV addition or a public proof of concept, and recheck NVD once analysis is complete.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – 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 Response Center: CVE-2026-118725 msrc.microsoft.com
- CVE Record CVE-2026-118725 www.cve.org
- Strix: CVE-2026-118725 www.strix.ai
- threatint: CVE-2026-118725 cve.threatint.com
- Microsoft November 2026 Patch Tuesday (Cybersecurity News) cybersecuritynews.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, 21:45.
Original description (NVD)
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to elevate privileges 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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