CVE-2025-59936
BaseFortify
Publication date: 2025-09-27
Last updated on: 2025-09-29
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nearform | get-jwks | 11.0.1 |
| nearform | get-jwks | 11.0.2 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-116 | The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability in get-jwks prior to version 11.0.2 involves cache poisoning in the JWKS key-fetching mechanism. Specifically, if the issuer (iss) claim is validated only after keys are retrieved from the cache, cached keys from an unexpected issuer can be reused. This allows an attacker to craft two JWTs: the first causes a chosen public key to be stored in the shared JWKS cache, and the second uses that cached key to pass signature validation for a targeted issuer value, effectively bypassing issuer validation.
How can this vulnerability impact me? :
This vulnerability can allow an attacker to bypass issuer validation by reusing cached keys from an unexpected issuer. This means that an attacker could potentially authenticate as a different issuer, leading to unauthorized access or actions within systems relying on get-jwks for JWT validation.
What immediate steps should I take to mitigate this vulnerability?
Upgrade get-jwks to version 11.0.2 or later, where the vulnerability has been patched. Additionally, ensure that the iss (issuer) claim validation is performed before retrieving keys from the JWKS cache to prevent cache poisoning attacks.