CVE-2025-9544 is a vulnerability classified under CWE-862 (Missing Authorization) affecting the Doppler Forms WordPress plugin through version 2.5.1. The issue arises because the plugin registers an AJAX action called install_extension without performing proper capability checks or nonce verification. This means that any authenticated user, even those assigned the Subscriber role with minimal privileges, can invoke this AJAX endpoint to install and activate additional Doppler Forms plugin extensions. The extensions that can be installed are limited to those whitelisted by the main Doppler Forms plugin, but this still represents a significant risk as it allows unauthorized modification of the plugin's functionality. The vulnerability does not require user interaction and can be exploited remotely over the network (AV:N). The attack complexity is low (AC:L), and only low privileges are required (PR:L). The vulnerability impacts the integrity of the WordPress site by enabling unauthorized plugin activation, but it does not affect confidentiality or availability. The CVSS v3.1 base score is 6.5, reflecting a medium severity. No patches or fixes are currently linked, and no known exploits have been reported in the wild. The vulnerability was published on October 29, 2025, and was reserved in August 2025. The lack of nonce and capability checks indicates a design flaw in the plugin's authorization logic, which should be addressed by implementing proper permission verification and nonce validation to prevent unauthorized AJAX calls.

For European organizations, this vulnerability poses a risk primarily to the integrity of WordPress-based websites using the Doppler Forms plugin. Unauthorized users with minimal privileges can escalate their capabilities to install and activate additional plugin extensions, potentially introducing malicious code or backdoors. This can lead to website defacement, data manipulation, or further compromise of the hosting environment. Organizations with subscriber or low-privilege user roles exposed to the internet are particularly vulnerable. The impact is heightened for entities relying on WordPress for critical business functions, customer interactions, or data collection. Although confidentiality and availability are not directly impacted, the integrity breach could facilitate subsequent attacks, including data exfiltration or ransomware deployment. The absence of known exploits suggests a window for proactive mitigation. European sectors such as e-commerce, media, and public services that extensively use WordPress plugins may face increased risk if this vulnerability is exploited.

1. Immediately restrict the assignment of Subscriber or low-privilege roles to trusted users only, minimizing the number of authenticated users who can exploit this vulnerability. 2. Monitor and audit all plugin installation and activation activities within WordPress to detect unauthorized changes promptly. 3. Implement Web Application Firewall (WAF) rules to block or challenge AJAX requests to the install_extension endpoint unless originating from trusted administrative users. 4. Disable or remove the Doppler Forms plugin if it is not essential or if no immediate patch is available. 5. Engage with the plugin vendor or community to obtain or develop patches that add proper capability checks and nonce verification to the install_extension AJAX action. 6. Educate site administrators and developers about the risks of missing authorization checks and encourage secure coding practices for WordPress plugin development. 7. Regularly update WordPress core and plugins to the latest versions once fixes are released to close this and other vulnerabilities. 8. Use role management plugins to enforce stricter access controls and prevent privilege escalation via plugin features.