Name: Microsoft Windows: CVE-2026-83778: Microsoft Internet Messaging API Remote Code Execution Vulnerability
Creator: Rapid7
Published: 2026-10-13T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-83778, CWE-122, CVSS 8.8, EPSS 0.00805

Heap-based buffer overflow in Microsoft Internet Messaging API allows an unauthorized attacker to execute code over a network.

CVSS Details

CVSS 3.1 Base Score: 8.8
CVSS 3.1 Vector: (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)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Microsoft Windows	—	2026-10 Cumulative Update for Microsoft Windows Server 2022, version 21H2 (KB5126655)2026-10 Cumulative Update for Microsoft Windows 10, version 21H2 (KB5126657)2026-10 Cumulative Update for Microsoft Windows 11, version 23H2 (KB5126653)2026-10 Cumulative Update for Microsoft Windows Server 2012 (KB5126835)2026-10 Cumulative Update for Microsoft Windows 11, version 24H2 (KB5127648)2026-10 Cumulative Update for Microsoft Windows Server 2016, version 1607 (KB5126868)2026-10 Cumulative Update for Microsoft Windows Server 2019, version 1809 (KB5126651)2026-10 Cumulative Update for Microsoft Windows 11, version 25H2 (KB5127648)2026-10 Cumulative Update for Microsoft Windows 11, version 26H1 (KB5127646)2026-10 Cumulative Update for Microsoft Windows Server 2022, version 22H2 (KB5126655)2026-10 Cumulative Update for Microsoft Windows Server 2012 R2 (KB5126836)2026-10 Cumulative Update for Microsoft Windows Server 2025, version 24H2 (KB5126646)2026-10 Cumulative Update for Microsoft Windows 10, version 1607 (KB5126868)2026-10 Cumulative Update for Microsoft Windows 10, version 1809 (KB5126651)	Oct 13, 2026	Oct 13, 2026

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CVSS Details

Covered by Rapid7

Prioritise with Active Threat Intelligence