Name: CVE-2026-20957: Integer Underflow (Wrap or Wraparound)
Creator: Rapid7
Published: 2026-01-13T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-20957, CVSS 7.8, EPSS 0.00091

Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVSS Details

CVSS 3.1 Base Score: 7.8
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Microsoft Office	—	Download and install Microsoft KB5002824Upgrade to the latest version of Microsoft OfficeDownload and install Microsoft KB5002831	Jan 13, 2026	Jan 13, 2026

Prioritize with Active Threat Intelligence

With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.

Explore Intelligence Hub

MDR Buyer's Guide

Global Threat Landscape Report

Grow your business

CVSS Details

Covered by Rapid7

Prioritize with Active Threat Intelligence