{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/microsoft.aspnetcore.authentication.negotiate--9.0.0--9.0.20/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:microsoft:aspnetcore:*:*:*:*:*:*:*:*"],"_cs_cves":[{"cvss":7.5,"id":"CVE-2026-70179"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Microsoft.AspNetCore.Authentication.Negotiate (\u003e= 10.0.0, \u003c= 10.0.12)","Microsoft.AspNetCore.Authentication.Negotiate (\u003e= 8.0.0, \u003c= 8.0.31)","Microsoft.AspNetCore.Authentication.Negotiate (\u003e= 9.0.0, \u003c= 9.0.20)"],"_cs_severities":["high"],"_cs_tags":["vulnerability","elevation-of-privilege","dotnet"],"_cs_type":"advisory","_cs_vendors":["Microsoft"],"content_html":"\u003cp\u003eMicrosoft has disclosed a high-severity elevation of privilege vulnerability (CVE-2026-70179) impacting the Microsoft.AspNetCore.Authentication.Negotiate package within .NET applications. The flaw manifests when LDAP claim resolution is enabled, as the library fails to properly verify the LDAP result against the Kerberos principal SID during authentication. This failure allows a user or attacker to gain the identity context of an unintended LDAP principal, potentially leading to unauthorized access to application resources and functions. The vulnerability affects .NET deployments on Windows, Linux, and macOS platforms. Successful exploitation requires an attacker to already possess a level of authenticated access within the environment, from which they can then elevate privileges to target sensitive LDAP principals. Defenders should prioritize updating the vulnerable package versions in all .NET projects to the patched releases (10.0.13, 8.0.32, or 9.0.21) and ensuring all affected self-contained applications are recompiled and redeployed.\u003c/p\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eThe vulnerability carries a CVSS score of 7.5 and affects any .NET enterprise application utilizing Negotiate LDAP authentication with claim resolution enabled. If exploited, an attacker can bypass intended security boundaries by assuming the identity of other LDAP principals, leading to unauthorized data access, administrative actions, or lateral movement within the application context. The impact is significant for applications that rely on LDAP identity resolution to manage sensitive user roles and access controls.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eIdentify all .NET projects in the environment using the Microsoft.AspNetCore.Authentication.Negotiate package via the \u003ccode\u003edotnet --info\u003c/code\u003e command or by auditing project files.\u003c/li\u003e\n\u003cli\u003eUpgrade the Microsoft.AspNetCore.Authentication.Negotiate package to the patched versions: 10.0.13, 8.0.32, or 9.0.21.\u003c/li\u003e\n\u003cli\u003eRecompile and redeploy all self-contained applications utilizing the affected versions to ensure the security fix is embedded in the application runtime.\u003c/li\u003e\n\u003cli\u003eReview authentication logs and LDAP access patterns for unusual identity claims that do not align with the established Kerberos principal SID for the associated user sessions.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-10-14T00:30:57Z","date_published":"2026-10-14T00:30:57Z","id":"https://feed.craftedsignal.io/briefs/2026-10-aspnet-core-eop/","summary":"An elevation of privilege vulnerability in the Microsoft.AspNetCore.Authentication.Negotiate package allows an attacker to misassociate an authenticated identity with an unintended LDAP principal due to improper validation of Kerberos principal SIDs.","title":"Microsoft.AspNetCore.Authentication.Negotiate Elevation of Privilege Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-10-aspnet-core-eop/"}],"language":"en","title":"CraftedSignal Threat Feed - Microsoft.AspNetCore.Authentication.Negotiate (\u003e= 9.0.0, \u003c= 9.0.20)","version":"https://jsonfeed.org/version/1.1"}