CVE-2026-59354 in the critical feed json
Spring Security OAuth2 Authorization Server: Insufficient validation of Dynamic Client Registration metadata
published 2026-08-27 2 mo ago modified 2026-09-01 2 mo ago also EUVD-2026-66977
- cvss
- 9.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
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).
Patch / fix
- VMware by Broadcom Spring Security (OAuth2 Authorization Server module) 7.0.5
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- VMware by Broadcom Spring Security (OAuth2 Authorization Server module)
Classification
- Weakness
-
- CWE-20 Improper Input Validation
- Technology feeds
References
-
spring.io
/security/cve-2026-59354
vendor-advisory
-
nvd.nist.gov
/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N&version=3.1
technical-description, us-government-resource, third-party-advisory
Sources
- CVE List CVE-2026-59354
- NVD CVE-2026-59354
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.