The SureForms plugin for WordPress, widely used for contact forms, custom forms, and calculators, contains a Cross-Site Request Forgery (CSRF) vulnerability identified as CVE-2025-12535. This vulnerability arises because the plugin distributes generic WordPress REST API nonces (wp_rest) to unauthenticated users through the 'wp_ajax_nopriv_rest-nonce' action. Normally, nonces are used to protect against CSRF by ensuring that requests originate from legitimate users. However, SureForms incorrectly uses generic REST nonces instead of form-specific nonces, which means that any unauthenticated attacker can obtain a valid nonce and use it to bypass CSRF protections on REST API endpoints that rely solely on nonce verification without additional authentication or authorization checks. This allows attackers to perform unauthorized actions, such as triggering the plugin’s post-submission hooks, which could lead to data manipulation or execution of unintended workflows. Furthermore, because the vulnerability affects REST endpoints, it might also impact other plugins that rely on similar nonce-based protections. The vulnerability affects all versions up to and including 1.13.1, with no patch currently available. The CVSS v3.1 base score is 5.3 (medium), reflecting that the attack vector is network-based, requires no privileges or user interaction, and impacts integrity but not confidentiality or availability. No known exploits have been reported in the wild as of the publication date. The root cause is the improper use of generic nonces for unauthenticated REST API access, which is a deviation from best practices that recommend form-specific nonces or additional authentication layers for sensitive operations.

For European organizations, this vulnerability poses a risk primarily to the integrity of data and operations handled through the SureForms plugin on WordPress sites. Attackers can exploit the CSRF bypass to submit unauthorized form data or trigger backend actions without authentication, potentially leading to data corruption, unauthorized workflow execution, or manipulation of form-related processes. While confidentiality and availability are not directly impacted, the integrity compromise can undermine trust in web applications, cause operational disruptions, or facilitate further attacks if chained with other vulnerabilities. Organizations relying on SureForms for customer interactions, lead generation, or internal workflows may face reputational damage and operational inefficiencies. Since the vulnerability affects unauthenticated REST API endpoints, public-facing WordPress sites are particularly vulnerable. The lack of known exploits reduces immediate risk, but the medium severity and ease of exploitation warrant proactive mitigation, especially in sectors with stringent data integrity requirements such as finance, healthcare, and e-commerce prevalent in Europe.

1. Monitor the SureForms plugin vendor announcements closely and apply security patches immediately once available. 2. Until a patch is released, implement additional server-side validation to enforce form-specific nonce checks rather than relying on generic REST API nonces. 3. Restrict REST API access to authenticated users where possible, especially for endpoints that trigger sensitive actions or workflows. 4. Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious REST API requests that could indicate CSRF exploitation attempts. 5. Conduct thorough code reviews and security testing on custom forms and REST API endpoints to ensure proper nonce usage and authentication enforcement. 6. Educate development teams about secure nonce implementation and the risks of exposing generic nonces to unauthenticated users. 7. Regularly audit WordPress plugins for security compliance and remove or replace plugins that do not follow best security practices. 8. Use security plugins that can monitor and alert on unusual REST API activity or unauthorized form submissions.