CVE-2020-15240— Regression in JWT Signature Validation
Quick assessment
Affected
auth0 omniauth-auth0
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Auth0 omniauth-auth0是美国Auth0公司的一个应用于Oauth认证的Ruby代码库。 omniautho-auth0 (rubygems) 2.3.0 版本至2.4.1版本之前存在数据伪造问题漏洞，该漏洞源于在使用“JWT验证器”时不正确地验证JWT令牌签名。攻击者可利用该漏洞绕过身份验证和授权。
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I. Basic Information for CVE-2020-15240
Vulnerability Information
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Vulnerability Title
Regression in JWT Signature Validation
Source: CVE Program / CVE List V5
Vulnerability 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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
认证机制不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
Auth0 omniauth-auth0 数据伪造问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Auth0 omniauth-auth0是美国Auth0公司的一个应用于Oauth认证的Ruby代码库。 omniautho-auth0 (rubygems) 2.3.0 版本至2.4.1版本之前存在数据伪造问题漏洞，该漏洞源于在使用“JWT验证器”时不正确地验证JWT令牌签名。攻击者可利用该漏洞绕过身份验证和授权。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| auth0 | omniauth-auth0 | >= 2.3.0, <2.4.1 | - |
|
II. Public POCs for CVE-2020-15240
| # | POC Description | Source Link | Shenlong Link |
|---|
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Patches & Fixes for CVE-2020-15240 (1)
Vendor Advisories for CVE-2020-15240 (1)
-
https://github.com/auth0/omniauth-auth0/security/advisories/GHSA-58r4-h6v8-jcvm x_refsource_CONFIRM
Other References for CVE-2020-15240 (1)
-
https://rubygems.org/gems/omniauth-auth0 x_refsource_MISC
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V. Comments for CVE-2020-15240
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