Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-56100

CVE-2026-56100HIGH

SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint

  AV  AC  AT  PR  UI  VC  VI  VA   CVSS    EPSS   %ile   KEV
   N   L   N   L   N   H   H   N    8.6   .0053   42.5     —

AFFECTED
  Product      Versions  Fixed
  SpringBlade  2.7.3 –   —

TIMELINE
  Jun 18  Reserved by VulnCheck
  Aug 28  Published (CNA: VulnCheck)
  Aug 29  EXPLOIT PUBLISHED — CVE-2026-56100 (SpringBlade). Public exploit reference added.
  Sep 24  EXPLOIT PUBLISHED — CVE-2026-56100 (SpringBlade). Public exploit reference added.

CWE-862 · CNA: VulnCheck · CVSS v4.0 · 5 references · NVD status: Deferred

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.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
June 18, 2026	Reserved	Reserved by VulnCheck
August 28, 2026	Published	Published (CNA: VulnCheck)
August 29, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-56100 (SpringBlade). Public exploit reference added.
September 24, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-56100 (SpringBlade). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
SpringBlade	SpringBlade	—	2.7.3	—

Weaknesses

CWE-862

References (5)

https://gist.github.com/sud0why/e73405057dd7414a8c221ef17e0d0059#file-cve-2026-56100-springblade-authbypass-en-md [technical-description, exploit]
https://github.com/chillzhuang/SpringBlade [product]
https://github.com/chillzhuang/SpringBlade/commit/c69b9547c942c697da2f3ee6a9265b6004abd645 [patch]
https://github.com/chillzhuang/SpringBlade/releases#release-v5.0.0
https://www.vulncheck.com/advisories/springblade-privilege-escalation-via-exposed-feign-endpoint [third-party-advisory]

Authoritative record: CVE-2026-56100 at cve.org

Vendors: springblade

Weaknesses: CWE-862

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-56100 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.