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

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

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.

Products include 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.

Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.

Is CVE-2024-21643 being exploited?

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

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-rv9j-c866-gp5h.