CVE-2026-56100 SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint
Authenticated attackers can escalate privileges to administrator by exploiting an unprotected Feign endpoint and hardcoded JWT keys in SpringBlade.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-56100?
CVE-2026-56100 is a high-severity vulnerability in SpringBlade, published on 28 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-862
Which versions are affected by CVE-2026-56100?
How do I fix CVE-2026-56100?
No fix has been published for CVE-2026-56100 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-56100 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-56100 exists.
Sources
Also known as GHSA-pmhv-3rpv-4cgh.