Privilege Escalation in SpringBlade Framework by Vulnerable Feign Endpoint

CVE-2026-56100

What is CVE-2026-56100?

The SpringBlade framework, specifically in versions 2.7.3 through 3.5.0, is susceptible to a privilege escalation vulnerability. This issue arises from an unprotected internal Feign user-creation endpoint, which is exposed without adequate authorization checks. Authenticated attackers can send crafted POST requests to create system administrator accounts. The vulnerability exploits the framework's authentication filter, which inadequately validates JWT parsing without verifying user roles or caller identity. Additionally, a hardcoded JWT signing key, found in publicly accessible JAR files, allows attackers to forge tokens, escalating privileges from low-privilege users to administrators. This flaw can lead to unauthorized data access across tenants and establish persistent backdoor access.

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