CVE-2025-24070

Weak authentication in ASP.NET Core & Visual Studio allows an unauthorized attacker to elevate privileges over a network.

Microsoft Security Advisory CVE-2025-24070: .NET Elevation of Privilege Vulnerability

Executive summary

Microsoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core 9.0, ASP.NET Core 8.0, ASP.NET Core 6.0, and ASP.NET Core 2.3. This advisory also provides guidance on what developers can do to update their applications to address this vulnerability.

A vulnerability exists in ASP.NET Core applications calling RefreshSignInAsync with an improperly authenticated user parameter that could allow an attacker to sign into another user's account, resulting in Elevation of Privilege.

Announcement

Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/348

Mitigation factors

Microsoft has not identified any mitigating factors for this vulnerability.

Affected software

• Any ASP.NET Core 9.0 application running on ASP.NET Core 9.0.2 or earlier.
• Any ASP.NET Core application running on ASP.NET Core 8.0.13 or earlier.
• Any ASP.NET Core application running on ASP.NET Core 6.0.36 or earlier.
• Any ASP.NET Core 2.x application consuming the package Microsoft.AspNetCore.Identity version 2.3.0 or earlier.

Affected Packages

The vulnerability affects any Microsoft .NET Core project if it uses any of affected packages versions listed below

| Package name | Affected version | Patched version | | --- | --- | --- | | Microsoft.AspNetCore.Identity | 2.3.0 | 2.3.1 |

ASP.NET Core 9

| Package name | Affected version | Patched version | | --- | --- | --- | | Microsoft.AspNetCore.App.Runtime.linux-arm | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.linux-arm64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.linux-musl-arm | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.linux-musl-x64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.linux-x64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.osx-arm64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.osx-x64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.win-arm | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.win-arm64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.win-x64 | >= 9.0.0, <= 9.0.2 | 9.0.3 | | Microsoft.AspNetCore.App.Runtime.win-x86 | >= 9.0.0, <= 9.0.2 | 9.0.3 |

ASP.NET Core 8

| Package name | Affected version | Patched version | | --- | --- | --- | | Microsoft.AspNetCore.App.Runtime.linux-arm | >= 8.0.0, <= 8.0.13 | 8.0.14 | | Microsoft.AspNetCore.App.Runtime.linux-arm64 | >= 8.0.0, <= 8.0.13 | 8.0.14 | |…

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 9.0.104 and .NET Runtime 9.0.3.Security Fix(es):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (CVE-2025-24070)

Bug Fix(es) and Enhancement(s):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (BZ#2349733)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 8.0.114 and .NET Runtime 8.0.14.Security Fix(es):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (CVE-2025-24070)

Bug Fix(es) and Enhancement(s):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (BZ#2349733)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Weak authentication in ASP.NET Core & Visual Studio allows an unauthorized attacker to elevate privileges over a network.

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 9.0.104 and .NET Runtime 9.0.3.Security Fix(es):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (CVE-2025-24070)

Bug Fix(es) and Enhancement(s):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (BZ#2349733)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 9.0.104 and .NET Runtime 9.0.3.Security Fix(es):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (CVE-2025-24070)

Bug Fix(es) and Enhancement(s):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (BZ#2349733)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 8.0.114 and .NET Runtime 8.0.14.Security Fix(es):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (CVE-2025-24070)

Bug Fix(es) and Enhancement(s):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (BZ#2349733)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 8.0.114 and .NET Runtime 8.0.14.Security Fix(es):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (CVE-2025-24070)

Bug Fix(es) and Enhancement(s):

• dotnet: Privilege Escalation Vulnerability in .NET SignInManager.RefreshSignInAsync Method (BZ#2349733)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Weak authentication in ASP.NET Core & Visual Studio allows an unauthorized attacker to elevate privileges over a network.

Zahid TOKAT discovered that .NET suffered from a weak authentication vulnerability. An attacker could possibly use this issue to elevate privileges.