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Privacy Statement Third-Party Cookies AcceptRejectManage cookies MSRC  Customer Guidance  Security Update Guide  Vulnerabilities  CVE-2026-45591 ASP.NET Core Denial of Service Vulnerability New On this page  CVE-2026-45591  Subscribe RSS PowerShell  API  CSAF Security Vulnerability Released: Jun 9, 2026 Assigning CNA Microsoft CVE.org link CVE-2026-45591  Impact Denial of Service Max Severity Important Weakness CWE-400: Uncontrolled Resource Consumption CVSS Source Microsoft Vector String CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C Metrics CVSS:3.1 7.5 / 6.5  Base score metrics: 7.5 / Temporal score metrics: 6.5  Expand all  Collapse all Metric Value   Base score metrics(8) Attack Vector Network Attack Complexity Low Privileges Required None User Interaction None Scope Unchanged Confidentiality None Integrity None Availability High   Temporal score metrics(3) Exploit Code Maturity Unproven Remediation Level Official Fix Report Confidence Confirmed Please see Common Vulnerability Scoring System for more information on the definition of these metrics. Executive Summary Uncontrolled resource consumption in ASP.NET Core allows an unauthorized attacker to deny service over a network. Exploitability The following table provides an exploitability assessment for this vulnerability at the time of original publication. Publicly disclosed No Exploited No Exploitability assessment Exploitation Less Likely Acknowledgements Anonymous Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgements for more information. Security Updates To determine the support lifecycle for your software, see the Microsoft Support Lifecycle. Release date Descending  Edit columns  Download  Filters  Product Family  Max Severity  Impact  Platform   Clear Release date  Product Platform Impact Max Severity Article Download Build Number Assigning CNA Title: Release date, Content: Jun 9, 2026 .NET 8.0 installed on Mac OS - Denial of Service Important Title: Knowledge Base Articles for .NET 8.0 installed on Mac OS, Content:, 1 link 5097149  Title: Download Security Update for .NET 8.0 installed on Mac OS, Content:, 1 link Security Update  Title: Build numbers, Content: 8.0.28 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 8.0 installed on Linux - Denial of Service Important Title: Knowledge Base Articles for .NET 8.0 installed on Linux, Content:, 1 link 5097149  Title: Download Security Update for .NET 8.0 installed on Linux, Content:, 1 link Security Update  Title: Build numbers, Content: 8.0.28 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 8.0 installed on Windows - Denial of Service Important Title: Knowledge Base Articles for .NET 8.0 installed on Windows, Content:, 1 link 5097149  Title: Download Security Update for .NET 8.0 installed on Windows, Content:, 1 link Security Update  Title: Build numbers, Content: 8.0.28 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 ASP.NET Core 8.0 - Denial of Service Important Title: Knowledge Base Articles for ASP.NET Core 8.0, Content:, 1 link 5097149  Title: Download Security Update for ASP.NET Core 8.0, Content:, 1 link Security Update  Title: Build numbers, Content: 8.0.28 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 10.0 installed on Linux - Denial of Service Important Title: Knowledge Base Articles for .NET 10.0 installed on Linux, Content:, 1 link 5097148  Title: Download Security Update for .NET 10.0 installed on Linux, Content:, 1 link Security Update  Title: Build numbers, Content: 10.0.9 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 ASP.NET Core 10.0 - Denial of Service Important Title: Knowledge Base Articles for ASP.NET Core 10.0, Content:, 1 link 5097148  Title: Download Security Update for ASP.NET Core 10.0, Content:, 1 link Security Update  Title: Build numbers, Content: 10.0.9 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 10.0 installed on Mac OS - Denial of Service Important Title: Knowledge Base Articles for .NET 10.0 installed on Mac OS, Content:, 1 link 5097148  Title: Download Security Update for .NET 10.0 installed on Mac OS, Content:, 1 link Security Update  Title: Build numbers, Content: 10.0.9 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 10.0 installed on Windows - Denial of Service Important Title: Knowledge Base Articles for .NET 10.0 installed on Windows, Content:, 1 link 5097148  Title: Download Security Update for .NET 10.0 installed on Windows, Content:, 1 link Security Update  Title: Build numbers, Content: 10.0.9 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 Microsoft Visual Studio 2026 version 18.6 - Denial of Service Important Title: Knowledge Base Articles for Microsoft Visual Studio 2026 version 18.6, Content:, 1 link Release Notes  Title: Download Security Update for Microsoft Visual Studio 2026 version 18.6, Content:, 1 link Security Update  Title: Build numbers, Content: 18.6.3 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 ASP.NET Core 9.0 - Denial of Service Important Title: Knowledge Base Articles for ASP.NET Core 9.0, Content:, 1 link 5097150  Title: Download Security Update for ASP.NET Core 9.0, Content:, 1 link Security Update  Title: Build numbers, Content: 9.0.17 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 9.0 installed on Windows - Denial of Service Important Title: Knowledge Base Articles for .NET 9.0 installed on Windows, Content:, 1 link 5097150  Title: Download Security Update for .NET 9.0 installed on Windows, Content:, 1 link Security Update  Title: Build numbers, Content: 9.0.17 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 9.0 installed on Linux - Denial of Service Important Title: Knowledge Base Articles for .NET 9.0 installed on Linux, Content:, 1 link 5097150  Title: Download Security Update for .NET 9.0 installed on Linux, Content:, 1 link Security Update  Title: Build numbers, Content: 9.0.17 Title: Assigning CNA, Content: Microsoft Title: Release date, Content: Jun 9, 2026 .NET 9.0 installed on Mac OS - Denial of Service Important Title: Knowledge Base Articles for .NET 9.0 installed on Mac OS, Content:, 1 link 5097150  Title: Download Security Update for .NET 9.0 installed on Mac OS, Content:, 1 link Security Update  Title: Build numbers, Content: 9.0.17 Title: Assigning CNA, Content: Microsoft All results loaded Loaded all 13 rows Disclaimer The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply. Revisions version revisionDate description 1.0 Jun 9, 2026 Information published.  How satisfied are you with the MSRC Security Update Guide? Rating  Broken  Bad  Below average  Average  Great!  Your Privacy Choices Consumer Health Privacy