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CVE-2026-90474

Status: DeferredHigh (7.6)—

MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

UI:R (interacción del usuario para interceptar código de autorización) + obtención de tokens de acceso = ejecución en cliente. CWE-287 (autenticación débil) permite usar credenciales/tokens obtenidos para acceder a cuentas víctima.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

User Account ManagementPrivileged Account ManagementMulti-factor AuthenticationApplication Developer GuidanceActive Directory ConfigurationUser Training

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Mcphubx — McphubAI

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-90474",
  "cveTags": [],
  "metrics": {
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          "role": "CISA Coordinator",
          "options": [
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              "automatable": "no"
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          "version": "2.0.3",
          "timestamp": "2026-09-15T16:57:39.875184Z"
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          "modifiedAttackRequirements": "NOT_DEFINED",
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          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
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  "published": "2026-09-12T11:16:34.483",
  "references": [
    {
      "url": "https://github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38",
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    {
      "lang": "en",
      "value": "MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges."
    }
  ],
  "lastModified": "2026-09-23T17:17:47.390",
  "sourceIdentifier": "disclosure@vulncheck.com"
}