CVE-2026-70179
High
Description
Authentication bypass by spoofing in ASP.NET Core allows an authorized attacker to elevate privileges over a network.
SeverityHigh
CVSS7.5
Exploit probability—
ProductMicrosoft.aspnetcore.authentication.negotiate
PublishedOct 13, 2026
First seenOct 13, 2026
Weakness typeCWE-290CWE-290
How to fix
Update
- Microsoft.AspNetCore.Authentication.Negotiate10.0.13, 8.0.32, 9.0.21 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Microsoft.AspNetCore.Authentication.NegotiateNuGet | 10.0.0 ≤ v < 10.0.13, 8.0.0 ≤ v < 8.0.32, 9.0.0 ≤ v < 9.0.21 | 10.0.13, 8.0.32, 9.0.21 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.