In certain IETF OAuth 2.0-related specifications, when the JSON Web Token Profile for OAuth 2.0 Client Authentication mechanism is used, there are ambiguities in the audience values of JWTs sent to authorization servers. The affected RFCs may include RFC 7523, and also RFC 7521, RFC 7522, RFC 9101 (JAR), and RFC 9126 (PAR).
Conclusion & alert: CVE-2025-27371 is rated Moderate Risk (45.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.26%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-11 | 0.05% | 0.26% | +0.21% |
| 2 | 2025-08-11 | 0.04% | 0.05% | +0.01% |
| 3 | 2025-07-30 | — | 0.04% | — |
Full EPSS history (7 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.9 | 3.1 | MEDIUM |
|
1.6 | 4.7 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||