# CVE-2026-47303: ASP.NET Core Elevation of Privilege Vulnerability

> An authentication bypass in ASP.NET Core allows authorized attackers to elevate privileges over the network, requiring immediate patching.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Jul 2026
- **Updated:** 28 Oct 2026
- **Also known as:** BIT-dotnet-2026-47303, BIT-dotnet-sdk-2026-47303, GHSA-2p3q-h3hg-jcqq, MINI-7v57-w296-3fc7, MINI-r7xw-m2c8-jghp, UBUNTU-CVE-2026-47303

## What is CVE-2026-47303?

CVE-2026-47303 is a high-severity authentication bypass vulnerability in Microsoft .Net, published on 14 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Authentication bypass by assumed-immutable data in ASP.NET Core allows an authorized attacker to elevate privileges over a network.

Weakness: CWE-90 (Improper Neutralization of Special Elements used in an LDAP Query), CWE-863 (Incorrect Authorization), CWE-302 (Authentication Bypass by Assumed-Immutable Data)

## Which versions are affected by CVE-2026-47303?

8 open source packages ship an affected version, including Microsoft.AspNetCore.Authentication.Negotiate, dotnet and dotnet-sdk. It affects 3 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Microsoft.AspNetCore.Authentication.Negotiate` | NuGet | From 10.0.0 | 10.0.10 |
| `Microsoft.AspNetCore.Authentication.Negotiate` | NuGet | From 10.0.0 | 10.0.10 |
| `Microsoft.AspNetCore.Authentication.Negotiate` | NuGet | From 8.0.0 | 8.0.29 |
| `Microsoft.AspNetCore.Authentication.Negotiate` | NuGet | From 8.0.0 | 8.0.29 |
| `Microsoft.AspNetCore.Authentication.Negotiate` | NuGet | From 9.0.0 | 9.0.18 |
| `Microsoft.AspNetCore.Authentication.Negotiate` | NuGet | From 9.0.0 | 9.0.18 |
| `dotnet` | Bitnami | From 8.0.0 | 8.0.29, 9.0.18, 10.0.6 |
| `dotnet-sdk` | Bitnami | From 8.0.0 | 8.0.29, 9.0.18, 10.0.6 |

Products: Microsoft .Net, Microsoft Visual Studio 2022, Microsoft Visual Studio 2026.

## How do I fix CVE-2026-47303?

Upgrade Microsoft.AspNetCore.Authentication.Negotiate to a fixed version for your release line: 10.0.10, 8.0.29 or 9.0.18.

## Is CVE-2026-47303 being exploited?

There is no known exploitation of CVE-2026-47303 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft .Net

- [CVE-2024-43498](https://insights.sbomify.com/CVE-2024-43498/): .NET and Visual Studio Remote Code Execution Vulnerability (critical 9.8)
- [CVE-2024-0057](https://insights.sbomify.com/CVE-2024-0057/): NET, .NET Framework, and Visual Studio Security Feature Bypass Vulnerability (critical 9.1)
- [CVE-2026-96957](https://insights.sbomify.com/CVE-2026-96957/): .NET Security Feature Bypass Vulnerability (high 8.8)
- [CVE-2026-69439](https://insights.sbomify.com/CVE-2026-69439/): .NET and Visual Studio Elevation of Privilege Vulnerability (high 8.8)
- [CVE-2026-71328](https://insights.sbomify.com/CVE-2026-71328/): .NET and Visual Studio Remote Code Execution Vulnerability (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-47303 and fix it if it is affected.

What it is: CVE-2026-47303 is a high-severity authentication bypass vulnerability in Microsoft .Net, published on 14 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-47303 in the wild and no public exploit code.

Affected packages and fixed versions:
- Microsoft.AspNetCore.Authentication.Negotiate (NuGet): affected from 10.0.0; fixed in 10.0.10
- Microsoft.AspNetCore.Authentication.Negotiate (NuGet): affected from 10.0.0; fixed in 10.0.10
- Microsoft.AspNetCore.Authentication.Negotiate (NuGet): affected from 8.0.0; fixed in 8.0.29
- Microsoft.AspNetCore.Authentication.Negotiate (NuGet): affected from 8.0.0; fixed in 8.0.29
- Microsoft.AspNetCore.Authentication.Negotiate (NuGet): affected from 9.0.0; fixed in 9.0.18
- Microsoft.AspNetCore.Authentication.Negotiate (NuGet): affected from 9.0.0; fixed in 9.0.18
- dotnet (Bitnami): affected from 8.0.0; fixed in 8.0.29, 9.0.18, 10.0.6
- dotnet-sdk (Bitnami): affected from 8.0.0; fixed in 8.0.29, 9.0.18, 10.0.6

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-47303/ (Markdown: https://insights.sbomify.com/CVE-2026-47303/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-47303
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-47303
- OSV: https://osv.dev/vulnerability/CVE-2026-47303

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-47303/
Summaries are generated and may contain mistakes; the official description above is the record.