CVE-2024-30547 identifies a DOM-based Cross-Site Scripting (XSS) vulnerability in the Shazdeh Header Image Slider plugin, specifically versions up to 0.3. This vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, classified under CWE-79. DOM-based XSS occurs when client-side scripts write untrusted data to the Document Object Model without proper sanitization, allowing attackers to execute arbitrary JavaScript in the context of the victim's browser. The vulnerability does not require authentication (PR:N) but does require user interaction (UI:R), such as clicking a crafted link or visiting a malicious page. The CVSS v3.1 score of 7.1 reflects a high severity, with network attack vector (AV:N), low attack complexity (AC:L), and impacts on confidentiality, integrity, and availability (C:L/I:L/A:L). Exploitation could lead to session hijacking, defacement, or distribution of malware, compromising user data and trust. Although no known exploits are currently reported in the wild, the vulnerability's presence in a popular WordPress plugin used for header image sliders makes it a notable risk for websites relying on this component. The lack of available patches at the time of reporting increases the urgency for mitigation. The vulnerability affects the plugin's handling of input during web page generation, emphasizing the need for secure coding practices such as input validation, output encoding, and use of security headers like Content Security Policy (CSP).

For European organizations, this vulnerability poses a significant risk to web applications using the Shazdeh Header Image Slider plugin. Successful exploitation can lead to unauthorized script execution in users' browsers, resulting in session hijacking, theft of sensitive information, defacement of websites, or distribution of malware. This can damage organizational reputation, lead to data breaches, and cause service disruptions. Given the widespread use of WordPress across Europe, especially in sectors like e-commerce, media, and government, the vulnerability could affect a broad range of targets. The impact extends beyond individual websites to potentially compromise user trust and violate data protection regulations such as GDPR if personal data is exposed. Additionally, the vulnerability's ability to affect confidentiality, integrity, and availability simultaneously increases the potential severity of attacks. Organizations relying on this plugin for their web presence must consider the risk of targeted attacks exploiting this flaw, particularly in countries with high WordPress market penetration and critical digital infrastructure.

1. Immediate removal or disabling of the Shazdeh Header Image Slider plugin until a secure patch is released. 2. If removal is not feasible, implement strict input validation and sanitization on all user-supplied data processed by the plugin, ensuring no untrusted input reaches the DOM without encoding. 3. Deploy Content Security Policy (CSP) headers to restrict the execution of inline scripts and reduce the risk of XSS exploitation. 4. Regularly monitor web application logs and user reports for suspicious activities indicative of XSS attacks. 5. Educate web administrators and developers on secure coding practices, emphasizing the dangers of DOM-based XSS. 6. Consider replacing the vulnerable plugin with a well-maintained alternative that follows secure development standards. 7. Keep all WordPress core, themes, and plugins updated to minimize exposure to known vulnerabilities. 8. Conduct periodic security assessments and penetration testing focused on client-side vulnerabilities. 9. Implement web application firewalls (WAF) with rules to detect and block XSS payloads targeting this plugin. 10. Prepare incident response plans to quickly address any exploitation attempts.