The vulnerability identified as CVE-2025-12158 affects the Simple User Capabilities WordPress plugin developed by tanvirahmed1984. The core issue is a missing authorization check in the suc_submit_capabilities() function, which is responsible for handling user capability submissions. Because this function does not verify whether the requester has the appropriate permissions, an unauthenticated attacker can invoke it to escalate privileges of any existing user account to administrator level. This flaw exists in all versions of the plugin up to and including version 1.0. The vulnerability is classified under CWE-862 (Missing Authorization) and has a CVSS v3.1 base score of 9.8, reflecting its critical nature. The attack vector is network-based (AV:N), requiring no privileges (PR:N) or user interaction (UI:N), and impacts confidentiality, integrity, and availability (C:H/I:H/A:H). Exploiting this vulnerability allows an attacker to gain full administrative control over the affected WordPress site, enabling actions such as installing malicious plugins, modifying content, stealing sensitive data, or disrupting service. No official patches or updates have been released at the time of publication, and no known exploits have been detected in the wild. The vulnerability was reserved on 2025-10-24 and published on 2025-11-04 by Wordfence. Due to the widespread use of WordPress and the plugin’s functionality, this vulnerability poses a significant threat to websites relying on this plugin for user role management.

For European organizations, this vulnerability presents a severe risk to websites and web applications running WordPress with the Simple User Capabilities plugin. Successful exploitation leads to full administrative access, allowing attackers to manipulate website content, exfiltrate sensitive data, deploy malware, or disrupt services. This can result in reputational damage, regulatory non-compliance (especially under GDPR), financial losses, and operational downtime. Organizations in sectors such as finance, healthcare, government, and e-commerce are particularly vulnerable due to the sensitive nature of their data and services. The ease of exploitation—requiring no authentication or user interaction—means that attackers can rapidly compromise multiple sites, potentially leading to widespread defacements or data breaches. Additionally, compromised administrator accounts can be used as footholds for lateral movement within corporate networks if the WordPress environment is integrated with internal systems. The lack of patches increases the urgency for immediate mitigation to prevent exploitation.

1. Immediately disable or uninstall the Simple User Capabilities plugin until a security patch is released. 2. Monitor all user accounts for unexpected privilege changes, especially elevation to administrator roles. 3. Implement Web Application Firewalls (WAFs) with custom rules to block suspicious requests targeting the suc_submit_capabilities() function or related endpoints. 4. Restrict access to WordPress administrative interfaces by IP whitelisting or VPN access where feasible. 5. Regularly audit installed plugins and remove any that are unnecessary or unmaintained. 6. Maintain up-to-date backups of WordPress sites to enable rapid restoration in case of compromise. 7. Follow vendor announcements closely and apply security updates immediately once available. 8. Employ intrusion detection systems (IDS) to detect anomalous behavior indicative of privilege escalation attempts. 9. Educate site administrators on the risks and signs of compromise related to privilege escalation vulnerabilities. 10. Consider deploying multi-factor authentication (MFA) for WordPress admin accounts to reduce impact if credentials are compromised.