CVE-2025-14002 is an authentication bypass vulnerability classified under CWE-287 affecting the whyun WPCOM Member plugin for WordPress, present in all versions up to and including 1.7.16. The vulnerability stems from weak OTP generation and verification mechanisms: the OTP consists of only 6 numeric digits, valid for 10 minutes, and the verification process lacks any rate limiting on attempts. This design flaw allows unauthenticated attackers to perform brute-force attacks against the OTP verification endpoint. If an attacker knows the victim's phone number, they can repeatedly guess the OTP until successful authentication is achieved. Since the OTP is the sole factor for authentication and no additional protections exist, the attacker can impersonate any user, including administrators, gaining full control over the WordPress site. The attack requires no prior authentication or user interaction beyond the victim receiving an SMS, which can be ignored or unnoticed. The vulnerability impacts confidentiality, integrity, and availability by enabling unauthorized access, potential data theft, content manipulation, or site takeover. Although no public exploits are currently reported, the simplicity of the attack vector and the lack of mitigations make exploitation likely once automated tools emerge. The CVSS 3.1 base score is 8.1, indicating a high severity with network attack vector, high impact, and no privileges or user interaction required.

For European organizations, this vulnerability poses a significant risk, especially for those relying on the WPCOM Member plugin to manage user authentication on WordPress sites. Successful exploitation can lead to unauthorized administrative access, enabling attackers to steal sensitive data, deface websites, inject malicious content, or deploy further malware. This can damage organizational reputation, lead to regulatory non-compliance (e.g., GDPR violations), and cause operational disruptions. Given the widespread use of WordPress in Europe for business and governmental websites, the impact can be broad. Organizations in sectors such as finance, healthcare, and public administration are particularly vulnerable due to the sensitive nature of their data and services. The lack of rate limiting and weak OTP design means automated brute-force attacks can be conducted at scale, increasing the likelihood of compromise. Additionally, the attack does not require user interaction, making phishing or social engineering unnecessary, which lowers the barrier for attackers.

1. Immediately monitor for updates or patches from the whyun vendor and apply them as soon as they become available. 2. If patches are not yet released, disable the WPCOM Member plugin or replace it with a more secure authentication solution. 3. Implement external rate limiting on OTP verification endpoints at the web server or application firewall level to prevent brute-force attempts. 4. Enhance OTP complexity by increasing length and including alphanumeric characters, and reduce the validity window to minimize attack surface. 5. Enable multi-factor authentication methods that do not rely solely on SMS OTP, such as authenticator apps or hardware tokens. 6. Monitor logs for repeated failed OTP attempts and unusual login patterns, especially from unknown IP addresses. 7. Educate users to report unexpected OTP messages and verify login notifications promptly. 8. Conduct regular security audits of WordPress plugins and remove unused or unsupported plugins to reduce attack vectors.