OpenID Connect up to 1.0 errata set 2 private_key_jwt authorization

Summaryinfo

A vulnerability was found in OpenID Connect up to 1.0 errata set 2. It has been declared as problematic. Impacted is an unknown function of the component private_key_jwt. Executing a manipulation can lead to authorization. This vulnerability is tracked as CVE-2025-27370. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in OpenID Connect up to 1.0 errata set 2. It has been declared as problematic. This vulnerability affects some unknown processing of the component private_key_jwt. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-863. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.

The advisory is available at openid.net. This vulnerability was named CVE-2025-27370 since 02/23/2025. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 06/01/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-5571). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• OpenID

Name

• Connect

Version

• 1.0 errata set 2

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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