SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint (CVE-2026-56100) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-56100

SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint

Answer in brief

CVE-2026-56100 records a Unknown severity vulnerability in SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint. The current sources do not mark it as known exploited. The current feed maps SpringBlade/SpringBlade (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 28, 2026Updated Aug 28, 2026Source checked Aug 28, 2026First seen by HOL Aug 28, 2026Material review Aug 28, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps SpringBlade/SpringBlade (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
SpringBlade/SpringBladegeneric	>=2.7.3 <5.0.0	5.0.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for SpringBlade/SpringBlade.
Review the reported fix. Update SpringBlade/SpringBlade to 5.0.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 28, 2026

Sources and claim methodology

Upstream source description

SpringBlade versions 2.7.3 through 3.5.0 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.

Quoted source text, attributed separately from HOL analysis.