CVE-2026-88156

CRITICAL

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

CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Published: 10/13/2026Modified: 10/15/2026

Related Intelligence (1)

CRITICALZero Day

Patch Tuesday - October 2026

Microsoft is publishing 1,413 own-product vulnerabilities on October 2026 Patch Tuesday , including 1,102 vulnerabilities in Windows. Anyone who enjoyed last month’s record-setting Patch Tuesday will love the October 2026 edition, because it’s much bigger still. As Rapid7 has noted over the course of 2026, there is every reason to suppose that vulnerability volumes will continue to rise. Microsoft

CVE-2026-96951CVE-2026-108398
Rapid7

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88156Vendor Advisory