What is CVE-2026-102857?

CVE-2026-102857 is a high-severity vulnerability in Microsoft 365 Apps For Enterprise, classified under Heap-based Buffer Overflow. CVSS score: 8.8/10. Published 2026-10-13.

How severe is CVE-2026-102857?

High severity. CVSS v3 base score is 8.8 out of 10.

Buffer overflow in Microsoft 365 Apps For Enterprise

CVE-2026-102857

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

Vulnerability class: Buffer Overflow

Published 2026-10-13 · last modified 2026-10-13.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Microsoft 365 Apps For Enterprise
Microsoft Office Ltsc 2021
Microsoft Office Ltsc 2024

Weakness classification (CWE)

CWE-122 — Heap-based Buffer Overflow
CWE-193 — Off-by-one Error

References

Microsoft Office Visio Remote Code Execution Vulnerability (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-102857?: CVE-2026-102857 is a high-severity vulnerability in Microsoft 365 Apps For Enterprise, classified under Heap-based Buffer Overflow. CVSS score: 8.8/10. Published 2026-10-13.
How severe is CVE-2026-102857?: High severity. CVSS v3 base score is 8.8 out of 10.