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CVE-2026-56100 (GCVE-0-2026-56100)

Vulnerability from cvelistv5 – Published: 2026-08-28 18:00 – Updated: 2026-08-29 11:47 X_Open Source
VLAI
Title
SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint
Summary
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 20:29 UTC
CWE
Impacted products
Vendor Product Version CPE status
SpringBlade SpringBlade Affected: 2.7.3 , < 5.0.0 (semver)
guessed Create a notification for this product.
Date Public
2026-07-30 00:00
Credits
Show details on NVD website

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