CVE-2026-70159 ASP.NET Core Denial of Service Vulnerability
An unauthorized attacker can cause a denial of service in ASP.NET Core SignalR by exploiting uncontrolled resource allocation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-70159?
CVE-2026-70159 is a high-severity denial of service vulnerability in Microsoft Visual Studio 2022 version 17.14, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Allocation of resources without limits or throttling in ASP.NET Core allows an unauthorized attacker to deny service over a network.
Weakness: CWE-770
Which versions are affected by CVE-2026-70159?
8 open source packages ship an affected version, including Microsoft.AspNetCore.SignalR.Common.
| Package | Affected | Fixed in |
|---|---|---|
Microsoft.AspNetCore.SignalR.Common NuGet | From 10.0.0 | 10.0.13 |
Microsoft.AspNetCore.SignalR.Common NuGet | From 10.0.0 | 10.0.13 |
Microsoft.AspNetCore.SignalR.Common NuGet | From 11.0.0-preview.5 | 11.0.0-rc.2 |
Microsoft.AspNetCore.SignalR.Common NuGet | From 11.0.0-preview.5 | 11.0.0-rc.2 |
Microsoft.AspNetCore.SignalR.Common NuGet | From 8.0.0 | 8.0.32 |
Microsoft.AspNetCore.SignalR.Common NuGet | From 8.0.0 | 8.0.32 |
2 more packages
Microsoft.AspNetCore.SignalR.Common NuGet | From 9.0.0 | 9.0.21 |
Microsoft.AspNetCore.SignalR.Common NuGet | From 9.0.0 | 9.0.21 |
How do I fix CVE-2026-70159?
Upgrade Microsoft.AspNetCore.SignalR.Common to a fixed version for your release line: 10.0.13, 11.0.0-rc.2, 8.0.32 or 9.0.21.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-70159 being exploited?
There is no known exploitation of CVE-2026-70159 in the wild and no public exploit code.
Sources
Also known as GHSA-334f-vvp4-7g6p, MINI-28hw-xv6x-f5mx, MINI-x9gf-h566-gm7w, UBUNTU-CVE-2026-70159.