CVE-2026-70257

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

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70257	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x64:*
	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x86:*
	cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x86:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x86:

History

15 Oct 2026, 16:18

Type	Values Removed	Values Added
First Time		Microsoft office 2024 Microsoft Microsoft 365 Apps Microsoft office 2021
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70257 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70257 - Vendor Advisory
CPE		cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x64: cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x86: cpe:2.3:a:microsoft:365_apps:-::::enterprise::x86:* cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x86: cpe:2.3:a:microsoft:365_apps:-::::enterprise::x64:* cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x64:

13 Oct 2026, 19:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 19:19

Updated : 2026-10-15 16:18

NVD link : CVE-2026-70257

Mitre link : CVE-2026-70257

CVE.ORG link : CVE-2026-70257

JSON object : View

Products Affected

microsoft

office_2024
office_2021
365_apps

CWE

CWE-122

Heap-based Buffer Overflow

CWE-190

Integer Overflow or Wraparound

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