CVE-2025-11880 is a stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the SM CountDown Widget plugin for WordPress, specifically versions 1.2 and earlier. The vulnerability arises from insufficient sanitization and escaping of user-supplied attributes in the plugin's smcountdown shortcode. Authenticated attackers with contributor-level permissions or higher can exploit this flaw by injecting arbitrary JavaScript code into pages or posts using the shortcode. Because the malicious script is stored within the content, it executes whenever any user accesses the compromised page, potentially allowing attackers to steal session cookies, perform actions on behalf of other users, or deface the website. The vulnerability is exploitable remotely over the network without user interaction, and the attack complexity is low, though it requires authentication with contributor or higher privileges. The CVSS 3.1 base score is 6.4, reflecting a medium severity with partial impact on confidentiality and integrity but no impact on availability. No public exploits have been reported yet, but the vulnerability's presence in a widely used CMS plugin makes it a significant risk if left unaddressed. The lack of official patches at the time of publication necessitates immediate mitigation measures by site administrators.

For European organizations, this vulnerability poses a moderate risk primarily to websites using the SM CountDown Widget plugin on WordPress platforms. Exploitation could lead to unauthorized disclosure of sensitive session information, enabling attackers to impersonate legitimate users or escalate privileges. This can result in data breaches, unauthorized content modifications, or defacement, damaging organizational reputation and potentially violating data protection regulations such as GDPR. Since the attack requires authenticated access at contributor level or above, insider threats or compromised user accounts increase the risk. The vulnerability does not affect system availability directly but compromises confidentiality and integrity, which are critical for maintaining trust and compliance. Organizations with customer-facing websites or intranet portals using this plugin should consider the threat significant enough to warrant prompt action.

1. Immediately update the SM CountDown Widget plugin to a patched version once available from the vendor. 2. Until a patch is released, restrict contributor-level and higher permissions to trusted users only, minimizing the risk of malicious shortcode injection. 3. Implement Web Application Firewall (WAF) rules to detect and block suspicious shortcode inputs containing script tags or JavaScript event handlers. 4. Conduct regular audits of existing content for injected scripts or suspicious shortcode usage, removing any malicious code found. 5. Employ Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on affected web pages. 6. Educate content contributors about safe content creation practices and the risks of embedding untrusted code. 7. Monitor logs for unusual activity related to shortcode usage or user behavior indicative of exploitation attempts. 8. Consider disabling or replacing the vulnerable plugin with alternative countdown solutions that follow secure coding practices.