CVE-2025-59936
get-jwks poisoned JWKS cache allows post-fetch issuer validation bypass
Description
get-jwks contains fetch utils for JWKS keys. In versions prior to 11.0.2, a vulnerability in get-jwks can lead to cache poisoning in the JWKS key-fetching mechanism. When the iss (issuer) claim is validated only after keys are retrieved from the cache, it is possible for cached keys from an unexpected issuer to be reused, resulting in a bypass of issuer validation. This design flaw enables a potential attack where a malicious actor crafts a pair of JWTs, the first one ensuring that a chosen public key is fetched and stored in the shared JWKS cache, and the second one leveraging that cached key to pass signature validation for a targeted iss value. The vulnerability will work only if the iss validation is done after the use of get-jwks for keys retrieval. This issue has been patched in version 11.0.2.
INFO
Published Date :
Sept. 27, 2025, 1:15 a.m.
Last Modified :
Sept. 27, 2025, 1:15 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2025-59936
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.0 | CRITICAL | [email protected] |
Solution
- Update get-jwks to version 11.0.2.
- Ensure issuer validation occurs before cache usage.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-59936.
| URL | Resource |
|---|---|
| https://github.com/nearform/get-jwks/commit/1706a177a80a1759fe68e3339dc5a219ce03ddb9 | |
| https://github.com/nearform/get-jwks/security/advisories/GHSA-qc2q-qhf3-235m |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-59936 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-59936
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-59936 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-59936 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Sep. 27, 2025
Action Type Old Value New Value Added Description get-jwks contains fetch utils for JWKS keys. In versions prior to 11.0.2, a vulnerability in get-jwks can lead to cache poisoning in the JWKS key-fetching mechanism. When the iss (issuer) claim is validated only after keys are retrieved from the cache, it is possible for cached keys from an unexpected issuer to be reused, resulting in a bypass of issuer validation. This design flaw enables a potential attack where a malicious actor crafts a pair of JWTs, the first one ensuring that a chosen public key is fetched and stored in the shared JWKS cache, and the second one leveraging that cached key to pass signature validation for a targeted iss value. The vulnerability will work only if the iss validation is done after the use of get-jwks for keys retrieval. This issue has been patched in version 11.0.2. Added CVSS V3 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L Added CWE CWE-116 Added Reference https://github.com/nearform/get-jwks/commit/1706a177a80a1759fe68e3339dc5a219ce03ddb9 Added Reference https://github.com/nearform/get-jwks/security/advisories/GHSA-qc2q-qhf3-235m