Spring Security OAuth2 Authorization Server: Insufficient validation of Dynamic Client Registration metadata (CVE-2026-59354) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-59354

Spring Security OAuth2 Authorization Server: Insufficient validation of Dynamic Client Registration metadata

Answer in brief

CVE-2026-59354 records a Unknown severity vulnerability in Spring Security OAuth2 Authorization Server: Insufficient validation of Dynamic Client Registration metadata. The current sources do not mark it as known exploited. The current feed maps VMware by Broadcom/Spring Security (OAuth2 Authorization Server module) (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 27, 2026Updated Aug 27, 2026Source checked Aug 27, 2026First seen by HOL Aug 27, 2026Material review Aug 27, 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: Not reported

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 VMware by Broadcom/Spring Security (OAuth2 Authorization Server module) (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
VMware by Broadcom/Spring Security (OAuth2 Authorization Server module)generic	7.0.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for VMware by Broadcom/Spring Security (OAuth2 Authorization Server module).
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Aug 27, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 27, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 27, 2026

Sources and claim methodology

Upstream source description

In versions of Spring Security's OAuth2 Authorization Server module 7.0.0 through 7.0.4, when Dynamic Client Registration is explicitly enabled, the registration endpoint performs insufficient validation of certain client metadata fields supplied by the registering client. An attacker who possesses a valid Initial Access Token can register a malicious client with crafted metadata, which, depending on server configuration and how the metadata is later rendered or used, may result in Stored Cross-Site Scripting (XSS), Privilege Escalation, or Server-Side Request Forgery (SSRF).

Quoted source text, attributed separately from HOL analysis.