CVE-2020-15240

Regression in JWT Signature Validation

Description

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.

Categories

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Vendor Advisory rubygems.org
Affected: auth0 omniauth-auth0
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2020-15240?
CVE-2020-15240 has been scored as a high severity vulnerability.
How to fix CVE-2020-15240?
To fix CVE-2020-15240, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-15240 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-15240 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-15240?
CVE-2020-15240 affects auth0 omniauth-auth0.
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