CVE-2026-22355 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the gregmolnar Simple XML Sitemap WordPress plugin, affecting all versions up to 1.3. The vulnerability allows an attacker to trick an authenticated user into submitting a forged request to the vulnerable plugin, which lacks adequate CSRF protections. This can lead to stored Cross-Site Scripting (XSS) attacks, where malicious scripts are injected and persist within the sitemap data managed by the plugin. The CVSS 3.1 base score of 7.1 reflects a high severity, with an attack vector of network (remote), low attack complexity, no privileges required, but user interaction needed. The scope is changed, indicating that exploitation can affect resources beyond the vulnerable component. The impact includes partial loss of confidentiality, integrity, and availability, as attackers can manipulate sitemap data, potentially redirect users or inject malicious content that compromises site visitors or administrators. Although no known exploits are reported in the wild, the vulnerability poses a significant risk due to the plugin's role in SEO and site indexing, which can be leveraged for further attacks or reputation damage. The vulnerability was reserved on January 7, 2026, and published on January 22, 2026, with no patch links currently available, indicating that immediate mitigation steps are critical. The plugin is widely used in WordPress environments, which are prevalent in European organizations, especially in sectors relying on web presence and digital marketing.

For European organizations, exploitation of this vulnerability could lead to unauthorized modification of sitemap data, enabling attackers to inject malicious scripts that execute in the context of site administrators or visitors. This compromises confidentiality by potentially exposing sensitive information through XSS payloads, integrity by altering sitemap content and SEO data, and availability by disrupting sitemap functionality critical for search engine indexing. The attack could facilitate further compromise, such as phishing or malware distribution, damaging organizational reputation and leading to regulatory compliance issues under GDPR if personal data is exposed. Given the widespread use of WordPress and SEO plugins in Europe, especially in countries with strong digital economies, the risk is significant. Organizations in sectors like e-commerce, media, and government websites are particularly vulnerable due to their reliance on accurate sitemap data and high web traffic. The lack of authentication requirements for exploitation increases the attack surface, and user interaction (e.g., visiting a malicious link) is the only barrier, which can be easily engineered through social engineering campaigns.

1. Monitor the vendor’s official channels for patch releases and apply updates to the Simple XML Sitemap plugin immediately upon availability. 2. Implement Web Application Firewall (WAF) rules to detect and block CSRF attack patterns targeting the sitemap plugin endpoints. 3. Enforce strict Content Security Policy (CSP) headers to mitigate the impact of stored XSS by restricting script execution sources. 4. Educate users and administrators about the risks of clicking on suspicious links to reduce the likelihood of successful CSRF exploitation. 5. Review and harden WordPress security configurations, including limiting plugin permissions and disabling unnecessary features. 6. Conduct regular security audits and penetration testing focusing on plugin vulnerabilities and CSRF protections. 7. Use security plugins that add CSRF tokens and nonce verification to forms and requests within WordPress. 8. Monitor logs for unusual sitemap modifications or administrative actions that could indicate exploitation attempts.