CVE-2026-78501

Improper neutralization of special elements used in a command ('command injection') in Microsoft 365 Copilot's Business Chat allows an unauthorized attacker to disclose information over a network.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78501	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:microsoft:365_copilot_chat:-:*:*:*:*:*:*:*

History

14 Oct 2026, 23:19

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~7.4~~	v2 : unknown v3 : 8.6

07 Oct 2026, 14:11

Type	Values Removed	Values Added
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78501 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78501 - Patch, Vendor Advisory
First Time		Microsoft 365 Copilot Chat Microsoft
CPE		cpe:2.3:a:microsoft:365_copilot_chat:-:::::::*

17 Sep 2026, 23:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 23:18

Updated : 2026-10-14 23:19

NVD link : CVE-2026-78501

Mitre link : CVE-2026-78501

CVE.ORG link : CVE-2026-78501

JSON object : View

Products Affected

microsoft

365_copilot_chat

CWE

CWE-77

Improper Neutralization of Special Elements used in a Command ('Command Injection')

CWE-923

Improper Restriction of Communication Channel to Intended Endpoints

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