CVE-2026-56100

SpringBlade versions from 2.7.3 up to but not including 5.0.0 contain a privilege escalation vulnerability that allows authenticated attackers to create system administrator accounts by sending crafted POST requests to an unprotected internal Feign user-creation endpoint exposed via @RestController without authorization checks. Attackers can exploit the gateway's authentication filter, which only validates JWT parsing without verifying user roles or caller identity, and leverage a hardcoded JWT signing key embedded in publicly available JARs to forge tokens and escalate privileges from a low-privilege user to administrator, enabling cross-tenant data pollution and persistent backdoor access.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/sud0why/e73405057dd7414a8c221ef17e0d0059#file-cve-2026-56100-springblade-authbypass-en-md
https://github.com/chillzhuang/SpringBlade
https://github.com/chillzhuang/SpringBlade/commit/c69b9547c942c697da2f3ee6a9265b6004abd645
https://github.com/chillzhuang/SpringBlade/releases#release-v5.0.0
https://www.vulncheck.com/advisories/springblade-privilege-escalation-via-exposed-feign-endpoint

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 20:18

Updated : 2026-09-16 13:42

NVD link : CVE-2026-56100

Mitre link : CVE-2026-56100

CVE.ORG link : CVE-2026-56100

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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