CVE-2022-2083: 
WordPress vulnerability analysis and mitigation

CVE-2022-2083 is an authentication bypass vulnerability affecting Simple Single Sign On WordPress plugin versions 4.1.0 and earlier, discovered in June 2022. The vulnerability stems from the plugin leaking its OAuth client_secret parameter, which could allow attackers to gain unauthorized access to WordPress sites using the plugin (WPScan, Lana Report).

The vulnerability occurs when the plugin redirects users to the OAuth server for authentication. During this process, the plugin exposes the client_secret parameter in the URL query string. This secret token should never be exposed as per OAuth 2.0 standards, particularly in the Authorization Code Grant flow. The plugin incorrectly includes both client_id and client_secret in the authorization request URL, allowing attackers to capture these credentials and use them to obtain unauthorized access tokens through the Client Credentials Grant flow (Lana Report). The vulnerability has been assigned a CVSS score of 8.2 (High) and is classified as CWE-287 (WPScan).

When exploited, this vulnerability allows attackers to authenticate themselves on the OAuth server using the exposed client credentials without requiring any user login credentials. Depending on the OAuth server settings, attackers could potentially gain administrative access to the WordPress site. The vulnerability enables unauthorized access to protected resources and could lead to complete site compromise (Lana Report).

The vulnerability is easily exploitable by capturing the client_secret from the authorization request URL. Proof-of-concept exploit code has been published that demonstrates how to obtain the client credentials and use them to generate valid access tokens. The exploit works particularly when the OAuth server has the Pro version installed that supports Client Credentials Grant Type authentication (WPScan, Lana Report).

As of the vulnerability disclosure, no official fix has been released for this vulnerability. Site administrators using the Simple Single Sign On plugin version 4.1.0 or earlier should consider disabling the plugin until a security patch is available (WPScan).