CVE-2026-21523

Time-of-check time-of-use (toctou) race condition in GitHub Copilot and Visual Studio allows an authorized attacker to execute code over a network.

CVSS v3 8.0 HIGH

8.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

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-2026-21523	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:microsoft:visual_studio_code:*:*:*:*:*:-:*:*

History

17 Jun 2026, 10:18

Type	Values Removed	Values Added
Summary		(es) Una condición de carrera de tipo time-of-check time-of-use (toctou) en GitHub Copilot y Visual Studio permite a un atacante autorizado ejecutar código a través de una red.

11 Feb 2026, 21:41

Type	Values Removed	Values Added
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21523 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21523 - Vendor Advisory
First Time		Microsoft visual Studio Code Microsoft
CPE		cpe:2.3:a:microsoft:visual_studio_code::::::-::*

10 Feb 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-10 18:16

Updated : 2026-06-17 10:18

NVD link : CVE-2026-21523

Mitre link : CVE-2026-21523

CVE.ORG link : CVE-2026-21523

JSON object : View

Products Affected

microsoft

visual_studio_code

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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