Bug 1890550 (CVE-2020-15240)

Summary:	CVE-2020-15240 rubygem-omniauth: regression in JWT signature validation
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	axilleas, extras-orphan, jaruga
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Hardware:	All
OS:	Linux
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Last Closed:	2021-10-28 05:27:27 UTC	Type:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Description Guilherme de Almeida Suckevicz 2020-10-22 13:47:12 UTC

omniauth-auth0 (rubygems) versions >= 2.3.0 and < 2.4.1 improperly validate the JWT token signature when using the `jwt_validator.verify` method. Improper validation of the JWT token signature can allow an attacker to bypass authentication and authorization. You are affected by this vulnerability if all of the following conditions apply: 1. You are using `omniauth-auth0`. 2. You are using `JWTValidator.verify` method directly OR you are not authenticating using the SDK’s default Authorization Code Flow. The issue is patched in version 2.4.1.

Reference:
https://github.com/auth0/omniauth-auth0/security/advisories/GHSA-58r4-h6v8-jcvm

Upstream patch:
https://github.com/auth0/omniauth-auth0/commit/fd3a14f4ccdfbc515d1121d6378ff88bf55a7a7a