Microsoft Office PowerPoint: Heap-based buffer overflow allows remote code execution
Summary
A heap-based buffer overflow in Microsoft Office PowerPoint allows an unauthorized attacker to execute code over the network. The attacker must get a user to open a crafted PowerPoint file, for example through an email attachment or download, and needs no privileges. As of publication, no exploitation or public exploit code is known, and NVD had not yet analysed the CVE.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 up to the build listed in the Microsoft advisory (exact build unknown)
- Office 365 for Mac: 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 (per third-party sources, not confirmed by the CNA record)
- Office LTSC for Mac 2021 and 2024: before 16.115.26110837 (per third-party sources, not confirmed by the CNA record)
Fixed in
- Microsoft 365 Apps for Enterprise: Unknown. The CNA record links to the update guide and does not give a build number.
- Office 365 for Mac: 16.115.26110837
- Office LTSC 2021: 16.0.14334.21048
- Office LTSC 2024: 16.0.17932.21140 (third-party source, verify with Microsoft)
- Office LTSC for Mac 2021 and 2024: 16.115.26110837 (third-party source, verify with Microsoft)
Workaround
No workaround or mitigation is documented in the sources reviewed. Unknown whether Microsoft recommends interim controls.
Exploitation
- CNA CVSS exploit maturity is "Unproven" (E:U).
- CISA SSVC: exploitation none, automatable no, technical impact total.
- No reports of in-the-wild exploitation, public proof-of-concept or CISA KEV entry were found at the time of research. This is not confirmation of absence.
Our recommendation
- Identify the Office edition, channel and build on all endpoints.
- Install the November 2026 Microsoft Office updates, and confirm the fixed Microsoft 365 build on the MSRC page.
- Keep email filtering and restrictions on opening Office files from untrusted sources in place.
- Monitor the CISA KEV catalogue for a change in exploitation status.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Response Center: CVE-2026-120001 msrc.microsoft.com
- CVE Program: CVE-2026-120001 record www.cve.org
- Microsoft Security Update Guide msrc.microsoft.com
- Strix: CVE-2026-120001 (secondary) www.strix.ai
- threatint: CVE-2026-120001 (secondary) cve.threatint.com
- Vulners: October 2026 PowerPoint batch check vulners.com
- Proofpoint: 2026 CVEs in email-based campaigns www.proofpoint.com
- Malwarebytes: CISA KEV addition of legacy PowerPoint flaw (January 2026) www.malwarebytes.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, 21:34.
Original description (NVD)
Heap-based buffer overflow in Microsoft Office PowerPoint 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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