User Impersonation Affecting microsoft.aspnetcore.authentication.negotiate package, versions [8.0.0,8.0.32)[9.0.0,9.0.21)[10.0.0,10.0.13)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DOTNET-MICROSOFTASPNETCOREAUTHENTICATIONNEGOTIATE-20936571
- published14 Oct 2026
- disclosed13 Oct 2026
- creditthegoldmandm
Introduced: 13 Oct 2026
NewCVE-2026-70179 (opens in a new tab)How to fix?
Upgrade Microsoft.AspNetCore.Authentication.Negotiate to version 8.0.32, 9.0.21, 10.0.13 or higher.
Overview
Affected versions of this package are vulnerable to User Impersonation in the LDAP claim resolution process. An attacker can gain unauthorized access or escalate privileges by exploiting the lack of verification between the LDAP result and the Kerberos principal SID.