# CVE-2026-120791: Microsoft Office Excel Remote Code Execution Vulnerability

Status: published. Published: 2026-11-10. Updated: 2026-11-10.

Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: microsoft) — https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-120791

## Affected products and versions

- Microsoft / Microsoft 365 Apps for Enterprise: ≥ 16.0.1; < https://aka.ms/OfficeSecurityReleases (affected, custom). Source: CNA: microsoft; platforms: 32-bit Systems, x64-based Systems
- Microsoft / Microsoft Office 365 for Mac: ≥ 1.0.0; < 16.115.26110837 (affected, custom). Source: CNA: microsoft
- Microsoft / Microsoft Office LTSC 2021: ≥ 16.0.1; < 16.0.14334.21048 (affected, custom). Source: CNA: microsoft; platforms: 32-bit Systems, x64-based Systems
- Microsoft / Microsoft Office LTSC 2024: ≥ 16.0.0; < 16.0.17932.21140 (affected, custom). Source: CNA: microsoft; platforms: 32-bit Systems, x64-based Systems
- Microsoft / Microsoft Office LTSC for Mac 2021: ≥ 16.0.1; < 16.115.26110837 (affected, custom). Source: CNA: microsoft
- Microsoft / Microsoft Office LTSC for Mac 2024: ≥ 16.0.0; < 16.115.26110837 (affected, custom). Source: CNA: microsoft
- Microsoft / Office Online Server: ≥ 16.0.0.0; < 16.0.10417.20236 (affected, custom). Source: CNA: microsoft

## Severity and prioritization

- CVSS 3.1: 8.8 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C; source: CNA: microsoft

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-122

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-120791 (CNA: microsoft; vendor-advisory, patch)

## Provenance

- CNA: microsoft: https://www.cve.org/CVERecord?id=CVE-2026-120791; retrieved 2026-11-10; source updated 2026-11-10

Revision: ccba1ff227c77ddd6566b1986e566becab7792eef72a2b2e2df89c2f2e9aee3c

Canonical: https://y2.dev/cve/CVE-2026-120791

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