SpringBlade versions 2.7.3 through 3.5.0 contain a privilege escalation vulnerability that allows authenticated attackers to create system… (CVE-2026-56100)

CVE-2026-56100 affects SpringBlade versions 2.7.3 through 3.5.0. The vulnerability is a privilege escalation issue where authenticated users can create system administrator accounts by sending crafted POST requests to an internal Feign user-creation endpoint exposed without authorization checks via @RestController. The gateway's authentication filter only validates JWT parsing but does not verify user roles or caller identity. A hardcoded JWT signing key embedded in publicly available JARs enables attackers to forge tokens, escalate privileges from low-privilege users to administrators, and maintain persistent unauthorized access, including cross-tenant data pollution.

Exploitation allows authenticated attackers to escalate privileges to system administrator level, enabling unauthorized creation of admin accounts. This can lead to cross-tenant data pollution and persistent backdoor access, severely compromising system integrity and confidentiality. The CVSS 3.1 score of 8.1 reflects high impact on confidentiality and integrity with network attack vector and low attack complexity.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to the affected endpoints and review JWT signing key management to prevent token forgery. Monitor for suspicious account creation activities and consider implementing additional authorization checks on internal endpoints.