# CVE-2024-21643: Microsoft.IdentityModel.Protocols.SignedHttpRequest remote code execution vulnerability

> Attackers can exploit default JKU trust in SignedHttpRequest to trigger SSRF, potentially leading to remote code execution or data exposure.

- **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L`)
- **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:** 10 Jan 2024
- **Updated:** 10 Jun 2025
- **Also known as:** GHSA-rv9j-c866-gp5h

## What is CVE-2024-21643?

CVE-2024-21643 is a high-severity server-side request forgery vulnerability in AzureAD azure-activedirectory-identitymodel-extensions-for-dotnet, published on 10 Jan 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

IdentityModel Extensions for .NET provide assemblies for web developers that wish to use federated identity providers for establishing the caller's identity. Anyone leveraging the `SignedHttpRequest`protocol or the `SignedHttpRequestValidator`is vulnerable. Microsoft.IdentityModel trusts the `jku`claim by default for the `SignedHttpRequest`protocol. This raises the possibility to make any remote or local `HTTP GET` request. The vulnerability has been fixed in Microsoft.IdentityModel.Protocols.SignedHttpRequest. Users should update all their Microsoft.IdentityModel versions to 7.1.2 (for 7x) or higher, 6.34.0 (for 6x) or higher.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2024-21643?

4 open source packages ship an affected version, including Microsoft.IdentityModel.Protocols.SignedHttpRequest. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Microsoft.IdentityModel.Protocols.SignedHttpRequest` | NuGet | All versions | 6.34.0 |
| `Microsoft.IdentityModel.Protocols.SignedHttpRequest` | NuGet | All versions | 6.34.0 |
| `Microsoft.IdentityModel.Protocols.SignedHttpRequest` | NuGet | From 7.0.0-preview | 7.1.2 |
| `Microsoft.IdentityModel.Protocols.SignedHttpRequest` | NuGet | From 7.0.0-preview | 7.1.2 |

Products: Microsoft Identitymodel Extensions.

## How do I fix CVE-2024-21643?

Upgrade Microsoft.IdentityModel.Protocols.SignedHttpRequest to a fixed version for your release line: 6.34.0 or 7.1.2.

## Is CVE-2024-21643 being exploited?

There is no known exploitation of CVE-2024-21643 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-21643 and fix it if it is affected.

What it is: CVE-2024-21643 is a high-severity server-side request forgery vulnerability in AzureAD azure-activedirectory-identitymodel-extensions-for-dotnet, published on 10 Jan 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-21643 in the wild and no public exploit code.

Affected packages and fixed versions:
- Microsoft.IdentityModel.Protocols.SignedHttpRequest (NuGet): affected all versions; fixed in 6.34.0
- Microsoft.IdentityModel.Protocols.SignedHttpRequest (NuGet): affected all versions; fixed in 6.34.0
- Microsoft.IdentityModel.Protocols.SignedHttpRequest (NuGet): affected from 7.0.0-preview; fixed in 7.1.2
- Microsoft.IdentityModel.Protocols.SignedHttpRequest (NuGet): affected from 7.0.0-preview; fixed in 7.1.2

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-2024-21643/ (Markdown: https://insights.sbomify.com/CVE-2024-21643/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-21643
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-21643
- OSV: https://osv.dev/vulnerability/CVE-2024-21643

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-21643/
Summaries are generated and may contain mistakes; the official description above is the record.