CVE-2026-23666 - Vulnerability Details - OpenCVE

Concurrent execution using shared resource with improper synchronization ('race condition') in .NET Framework allows an unauthorized attacker to deny service over a network.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Vendors	Products
Microsoft	.net

No data.

No data.

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23666
https://nvd.nist.gov/vuln/detail/CVE-2026-23666
https://www.cve.org/CVERecord?id=CVE-2026-23666

History

Wed, 15 Apr 2026 00:15:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-366
References		https://nvd.nist.gov/vuln/detail/CVE-2026-23666 https://www.cve.org/CVERecord?id=CVE-2026-23666
Metrics	threat_severity `None`	threat_severity `Important`

Tue, 14 Apr 2026 17:30:00 +0000

Type	Values Removed	Values Added
Description		Concurrent execution using shared resource with improper synchronization ('race condition') in .NET Framework allows an unauthorized attacker to deny service over a network.
Title		.NET Framework Denial of Service Vulnerability
First Time appeared		Microsoft Microsoft .net
Weaknesses		CWE-755
CPEs		cpe:2.3:a:microsoft:.net::::::::
Vendors & Products		Microsoft Microsoft .net
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23666
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-04-14T16:57:53.069Z

Updated: 2026-04-14T16:57:53.069Z

Reserved: 2026-01-14T16:59:33.464Z

Link: CVE-2026-23666

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-04-14T18:16:44.507

Modified: 2026-04-14T18:16:44.507

Link: CVE-2026-23666

Redhat

Severity : Important

Publid Date: 2026-04-14T16:57:53Z

Links: CVE-2026-23666 - Bugzilla

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