CVE-2025-6003 is a medium-severity vulnerability affecting the WordPress Single Sign-On (SSO) plugin developed by cyberlord92, specifically the Single Site Standard edition. The vulnerability arises from an incorrect authorization check (CWE-863) in the plugin's code, where a capability check is misconfigured or missing in a critical function. This flaw allows unauthenticated attackers to bypass intended access controls and extract sensitive data that should be restricted to certain users or roles. The affected versions include all versions up to and including the *.5.3 releases, indicating a broad impact across all currently deployed versions prior to a patch. The vulnerability does not require any user interaction or privileges, and can be exploited remotely over the network (AV:N, AC:L, PR:N, UI:N). The impact is limited to confidentiality, as attackers can read restricted site content but cannot modify data or disrupt availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability was published on June 12, 2025, and is tracked under CWE-863, which relates to improper authorization checks that allow unauthorized access to resources. Given the widespread use of WordPress and the popularity of SSO plugins for managing user authentication, this vulnerability poses a significant risk to websites relying on this plugin for access control, potentially exposing sensitive or proprietary content to unauthorized parties.

For European organizations, the impact of CVE-2025-6003 can be significant, especially for those using the cyberlord92 WordPress Single Sign-On plugin to manage user authentication and access control. Unauthorized disclosure of restricted content could lead to exposure of sensitive business information, internal communications, or customer data, potentially violating GDPR and other data protection regulations. This could result in reputational damage, regulatory fines, and loss of customer trust. Organizations in sectors such as finance, healthcare, government, and media, which often rely on WordPress for content management and use SSO for streamlined user access, are particularly at risk. Since the vulnerability allows unauthenticated attackers to access restricted content without any user interaction, it increases the likelihood of automated scanning and exploitation attempts. Although the vulnerability does not allow modification or disruption of services, the confidentiality breach alone can have serious consequences, including intellectual property theft and competitive disadvantage. The absence of known exploits in the wild currently provides a window for mitigation, but the ease of exploitation (no authentication or user interaction required) suggests that attackers could develop exploits rapidly once awareness spreads.

1. Immediate mitigation should focus on disabling or uninstalling the affected WordPress Single Sign-On plugin until a patched version is released. 2. Monitor official cyberlord92 and WordPress plugin repositories for updates or patches addressing CVE-2025-6003 and apply them promptly. 3. Implement Web Application Firewall (WAF) rules to detect and block suspicious requests targeting the SSO plugin endpoints, especially those attempting to access restricted content without proper authentication. 4. Conduct thorough access control audits on WordPress installations to ensure that sensitive content is not inadvertently exposed through other plugins or misconfigurations. 5. Employ network-level monitoring and anomaly detection to identify unusual access patterns indicative of exploitation attempts. 6. For organizations unable to immediately patch or disable the plugin, consider restricting access to the WordPress admin and SSO plugin URLs via IP whitelisting or VPN access to reduce exposure. 7. Educate site administrators on the risks of unauthorized access and encourage regular review of user roles and permissions to minimize potential damage. 8. Maintain regular backups of site content and configurations to enable recovery in case of compromise.