RubySec

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CVE-2020-15240 (omniauth-auth0): Regression in JWT Signature Validation

ADVISORIES

GEM

omniauth-auth0

SEVERITY

CVSS v3: 7.4 (High)

UNAFFECTED VERSIONS

  • < 2.3.0

PATCHED VERSIONS

  • >= 2.4.1

DESCRIPTION

Overview

Versions after and including 2.3.0 are improperly validating the JWT token signature when using the JWTValidator.verify method. Improper validation of the JWT token signature when not using the default Authorization Code Flow can allow an attacker to bypass authentication and authorization.

Am I affected?

You are affected by this vulnerability if all of the following conditions apply:

  • You are using omniauth-auth0.
  • You are using JWTValidator.verify method directly OR you are not authenticating using the SDK’s default Authorization Code Flow.

How to fix that?

Upgrade to version 2.4.1.

Will this update impact my users?

The fix provided in this version will not affect your users.