ASP.NET Core Elevation of Privilege Vulnerability

Source data

Overview

Authentication bypass by spoofing in ASP.NET Core allows an authorized attacker to elevate privileges over a network.

Impact & technical details

Elevation of Privilege

What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain ELEVATED privileges, which may allow them to perform actions beyond their original permissions.

According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability? Successful exploitation of this vulnerability requires an attacker to have a deep understanding of the system and the ability to manipulate its components to trigger a specific condition. Successful exploitation is not guaranteed and depends on a combination of factors that may include the environment, system configuration, and the presence of additional security measures.

CVSS base score

7.5 / 10

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Highest base score supplied by MSRC for this record; the vector belongs to that score. Ratings can vary by product. Microsoft Important is displayed as High; Moderate is displayed as Medium.

Affected products

• Microsoft Visual Studio 2022 version 17.14
• Microsoft Visual Studio 2026 version 18.10
• Microsoft.AspNetCore.Authentication.Negotiate on .NET 10.0 runtime installed on Linux
• Microsoft.AspNetCore.Authentication.Negotiate on .NET 10.0 runtime installed on Mac OS
• Microsoft.AspNetCore.Authentication.Negotiate on .NET 10.0 runtime installed on Windows
• Microsoft.AspNetCore.Authentication.Negotiate on .NET 8.0 runtime installed on Linux
• Microsoft.AspNetCore.Authentication.Negotiate on .NET 8.0 runtime installed on Mac OS
• Microsoft.AspNetCore.Authentication.Negotiate on .NET 8.0 runtime installed on Windows

Source guidance

Remediation

• Release Notes

At least one Microsoft vendor-fix reference is available. Check each affected product for its applicable update, prerequisites, and supported version.

Authoritative sources & updates

Findings and update information come from the linked publishers. GTP compiles the public record and provides the recommendation above. CVSS ratings shown here come from Microsoft. NVD references provide additional public context.

• Microsoft Security Response Center (opens in a new tab)
• Microsoft security update · Release Notes (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)
• Microsoft security update · Release Notes (opens in a new tab)
• Microsoft remediation guidance (opens in a new tab)