PT-2026-58253 · Microsoft · Malware Protection Engine

Published 2026-07-14 · Updated 2026-07-14 · CVE-2026-55011

NVD

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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

Fix

Integer Underflow

Weakness Enumeration

CWE-191

Related Identifiers

CVE-2026-55011

Affected Products

Malware Protection Engine

References · 2

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55011 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-55011 · Security Note