IdentityServer3 2.4.x, 2.5.x, and 2.6.x before 2.6.1 has XSS in an Angular expression on the authorize response page, which might allow remote attackers to obtain sensitive information about the IdentityServer authorization response.
Conclusion & alert: CVE-2017-12677 is rated Moderate Risk (46/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.04%). 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 | 2026-06-15 | 0.23% | 1.04% | +0.81% |
| 2 | 2025-03-17 | 0.09% | 0.23% | +0.14% |
| 3 | 2023-03-07 | — | 0.09% | — |
Full EPSS history (5 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.1 | 3.0 | MEDIUM |
|
2.8 | 2.7 | [email protected] |
| 4.3 | 2.0 | MEDIUM |
|
8.6 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| identityserver | identityserver3 | 2.4.0 | cpe:2.3:a:identityserver:identityserver3:2.4.0:*:*:*:*:*:*:* |
| identityserver | identityserver3 | 2.5.0 | cpe:2.3:a:identityserver:identityserver3:2.5.0:*:*:*:*:*:*:* |
| identityserver | identityserver3 | 2.5.1 | cpe:2.3:a:identityserver:identityserver3:2.5.1:*:*:*:*:*:*:* |
| identityserver | identityserver3 | 2.5.2 | cpe:2.3:a:identityserver:identityserver3:2.5.2:*:*:*:*:*:*:* |
| identityserver | identityserver3 | 2.5.3 | cpe:2.3:a:identityserver:identityserver3:2.5.3:*:*:*:*:*:*:* |
| identityserver | identityserver3 | 2.6.0 | cpe:2.3:a:identityserver:identityserver3:2.6.0:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/IdentityServer/IdentityServer3/releases/tag/2.6.1 | Third Party Advisory |