CVE-2026-0862 is a reflected Cross-Site Scripting (XSS) vulnerability identified in the Save as PDF Plugin by PDFCrowd for WordPress, affecting all versions up to and including 4.5.5. The root cause is insufficient sanitization and escaping of the 'options' parameter during web page generation, which allows unauthenticated attackers to inject malicious JavaScript code. This vulnerability is exploitable only if the PDFCrowd API key is either blank (the default 'demo mode' configuration) or known to the attacker. An attacker can craft a malicious URL containing a payload in the 'options' parameter and trick a user into clicking it, causing the injected script to execute in the victim's browser context. This can lead to session hijacking, credential theft, or other client-side attacks. The vulnerability has a CVSS 3.1 base score of 6.1, indicating medium severity, with attack vector as network, low attack complexity, no privileges required, but requiring user interaction. The scope is changed because the attack affects the user’s browser environment rather than the server directly. No patches or known exploits are currently reported, but the default insecure configuration increases risk. The plugin is widely used in WordPress environments, making this a relevant threat for websites relying on PDFCrowd’s PDF generation capabilities without proper API key configuration or input validation.

For European organizations, this vulnerability poses a risk primarily to websites using the Save as PDF Plugin by PDFCrowd with default or exposed API keys. Successful exploitation could lead to client-side attacks such as session hijacking, theft of authentication tokens, or execution of arbitrary scripts in users’ browsers. This can compromise user data confidentiality and integrity, damage organizational reputation, and potentially facilitate further attacks like phishing or malware distribution. Since the attack requires user interaction, the impact depends on user awareness and security training. Organizations in sectors with high web traffic or sensitive user data (e.g., e-commerce, government portals, financial services) are at greater risk. Additionally, the vulnerability could be leveraged to bypass security controls or inject malicious content into trusted websites, undermining trust and compliance with data protection regulations such as GDPR.

1. Immediately configure the PDFCrowd plugin with a strong, unique API key instead of using the default blank (demo) key to prevent unauthorized exploitation. 2. Implement strict input validation and output encoding on the 'options' parameter to neutralize malicious scripts before rendering. 3. Monitor web server and application logs for suspicious requests containing unusual or encoded payloads targeting the 'options' parameter. 4. Educate users and administrators about the risks of clicking on untrusted links, especially those that interact with PDF generation features. 5. If possible, update or patch the plugin once a fix is released by the vendor; in the meantime, consider disabling the plugin if not essential. 6. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts on affected web pages. 7. Conduct regular security assessments and penetration tests focusing on web application input handling and third-party plugins.