CVE-2026-109468: ASP.NET Core Denial of Service Vulnerability

Overview

Severity

High (CVSS 7.5)

CVSS Vector

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

Category

Denial of Service

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Oct

Released

2026-10-15

Description

Allocation of resources without limits or throttling in ASP.NET Core allows an unauthorized attacker to deny service over a network.

Affected Products (11)

Other

• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 10.0 installed on Windows
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 10.0 installed on Linux
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 10.0 installed on Mac OS
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 8.0 installed on Windows
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 8.0 installed on Linux
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 8.0 installed on Mac OS
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 9.0 installed on Windows
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 9.0 installed on Linux
• Microsoft.AspNetCore.SignalR.Protocols.MessagePack on .NET 9.0 installed on Mac OS

Developer Tools

• Microsoft Visual Studio 2026 version 18.10
• Microsoft Visual Studio 2022 version 17.14

Security Updates (1)

• Release Notes

Acknowledgments

thegoldmandm, Piotr Pietruszewski

Revision History

• 2026-10-15: Information published.