CVE-2026-56677

HIGHPre-NVD 8.68.6—
EchelonGraph scoreHIGH confidence

Score 8.6 from GitHub Security Advisory (severity: HIGH) published 2026-08-17. a secondary CVSS source baseline 8.6; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this weekElevated
8.6EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.6Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

9Router is an AI router & token saver. In 0.5.4 and earlier, the POST /api/auth/oidc/test endpoint in src/app/api/auth/oidc/test/route.js passes the user-controlled issuerUrl parameter to fetchOidcDiscovery() in src/lib/auth/oidc.js without restricting private or loopback destinations, allowing unauthenticated attackers when dashboard login is disabled to scan internal services and reflect OIDC discovery fields including token_endpoint and jwks_uri.

CVSS v3
8.6
EG Score
8.6(high)
EG Risk
70(Attend)
EG Risk 70/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity86% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
19%
KEV
Not listed

Published

August 17, 2026

Last Modified

August 18, 2026

Advisory Details (1)

Auto-updated Aug 17, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Authenticated Server-Side Request Forgery (SSRF) via OIDC Provider Test Endpoint · Advisory · decolua/9router · GitHub

https://github.com/decolua/9router/security/advisories/GHSA-8g4w-4ffg-8vgx

Vendor Advisories for CVE-2026-56677(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
npm9router—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
9router———

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 17× in last 7d / 17× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-20 22:55 UTCEPSS rescore
  2. 2026-08-20 20:42 UTCGHSA enrichment
  3. 2026-08-20 07:42 UTCGHSA enrichment
  4. 2026-08-19 18:43 UTCEG score recompute
  5. 2026-08-19 18:43 UTCGHSA enrichment
  6. 2026-08-19 17:04 UTCEPSS rescore
  7. 2026-08-19 05:42 UTCGHSA enrichment
  8. 2026-08-18 16:43 UTCEG score recompute
  9. 2026-08-18 16:43 UTCGHSA enrichment
  10. 2026-08-18 15:45 UTCEG score recompute
  11. 2026-08-18 15:45 UTCGHSA enrichment
  12. 2026-08-18 13:48 UTCEPSS rescore
  13. 2026-08-18 11:23 UTCGHSA enrichment
  14. 2026-08-17 22:22 UTCEG score recompute
  15. 2026-08-17 22:22 UTCGHSA enrichment
  16. 2026-08-17 21:30 UTCEG score recompute
  17. 2026-08-17 21:29 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-56677?
CVE-2026-56677 is a high vulnerability published on August 17, 2026. 9Router is an AI router & token saver. In 0.5.4 and earlier, the POST /api/auth/oidc/test endpoint in src/app/api/auth/oidc/test/route.js passes the user-controlled issuerUrl parameter to fetchOidcDiscovery() in src/lib/auth/oidc.js without restricting private or loopback destinations, allowing…
When was CVE-2026-56677 disclosed?
CVE-2026-56677 was first published in the National Vulnerability Database on August 17, 2026, with the most recent update on August 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56677 actively exploited?
CVE-2026-56677 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 80.6% of all scored CVEs.
What is the CVSS score of CVE-2026-56677?
CVE-2026-56677 has a CVSS v3 base score of 8.6 (NVD).
How do I remediate CVE-2026-56677?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56677, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-56677

Explore →

Is Your Infrastructure Affected by CVE-2026-56677?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs