CVE-2025-31840 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the digireturn Simple Fixed Notice plugin, specifically versions up to 1.6. CSRF vulnerabilities occur when a web application does not properly verify that requests made to it are intentional and authorized by the user, allowing attackers to craft malicious web pages that cause authenticated users to unknowingly execute unwanted actions. The affected product, Simple Fixed Notice, is a plugin used to manage cookie notices on websites, commonly integrated into content management systems such as WordPress. The vulnerability arises because the plugin fails to implement adequate anti-CSRF tokens or other verification mechanisms to validate the legitimacy of requests that modify its settings or behavior. Although no exploits have been reported in the wild, the risk remains that attackers could leverage this flaw to alter cookie notice configurations or other plugin settings by tricking logged-in administrators or users with sufficient privileges into visiting malicious websites. The vulnerability does not have an assigned CVSS score, and no official patches have been released at the time of publication. The attack requires the victim to be authenticated on the target site and to interact with a malicious webpage, limiting the ease of exploitation. However, successful exploitation could compromise the integrity of the plugin's configuration and potentially impact compliance with cookie consent regulations. The vulnerability was published on April 1, 2025, by Patchstack, and the affected versions include all up to 1.6. No CWE identifiers or detailed technical mitigations are provided in the initial disclosure.

The primary impact of this CSRF vulnerability is on the integrity of the affected web application’s configuration, specifically the Simple Fixed Notice plugin. An attacker exploiting this flaw could cause authenticated users to unknowingly change cookie notice settings, potentially disabling or altering consent mechanisms. This could lead to non-compliance with privacy regulations such as GDPR or CCPA, exposing organizations to legal and reputational risks. While the vulnerability does not directly compromise confidentiality or availability, the unauthorized changes could undermine user trust and regulatory adherence. Since exploitation requires user authentication and interaction, the scope is limited to sites where users with sufficient privileges are targeted. Organizations relying on this plugin for cookie management on high-traffic or regulated websites face increased risk. The absence of known exploits suggests the threat is currently theoretical but could become practical if weaponized. Overall, the impact is moderate but significant for organizations prioritizing privacy compliance and website integrity.

Given the lack of an official patch, organizations should implement immediate mitigations to reduce risk. First, enforce strict user authentication and limit administrative access to trusted personnel only. Implement web application firewall (WAF) rules to detect and block suspicious cross-site requests targeting the plugin’s endpoints. If possible, add custom CSRF tokens or nonce verification to the plugin’s forms and actions to ensure requests originate from legitimate users. Educate users with administrative privileges about the risks of visiting untrusted websites while logged in. Monitor logs for unusual changes to cookie notice settings that could indicate exploitation attempts. Consider temporarily disabling or replacing the Simple Fixed Notice plugin with an alternative that includes robust CSRF protections until an official patch is released. Regularly check for updates from the vendor and apply patches promptly once available. Additionally, review overall site security posture to minimize attack surface and ensure compliance with privacy regulations.