An incomplete fix was found in Keycloak Core patch. An attacker can steal authorization codes or tokens from clients using a wildcard in the JARM response mode "form_post.jwt". It is observed that changing the response_mode parameter in the original proof of concept from "form_post" to "form_post.jwt" can bypass the security patch implemented to address CVE-2023-6134.
{
"cwe_ids": [
"CWE-601"
],
"github_reviewed": true,
"github_reviewed_at": "2024-01-23T14:43:50Z",
"nvd_published_at": null,
"severity": "MODERATE"
}