CVE-2025-23903 is a high-severity reflected Cross-Site Scripting (XSS) vulnerability identified in the NotFound Local Shipping Labels plugin for WooCommerce, a widely used e-commerce platform plugin for WordPress. The vulnerability arises from improper neutralization of input during web page generation, classified under CWE-79. Specifically, the plugin fails to adequately sanitize user-supplied input before reflecting it in web pages, allowing attackers to inject malicious scripts. This reflected XSS can be triggered when a crafted URL or input is processed by the plugin and returned in the HTTP response without proper encoding or validation. The CVSS 3.1 base score of 7.1 reflects a network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:R). The scope is changed (S:C), indicating that the vulnerability can affect components beyond the initially vulnerable component. The impact includes low confidentiality, integrity, and availability impacts individually, but combined they can enable session hijacking, credential theft, or unauthorized actions on behalf of a user. No known exploits are currently reported in the wild, and no patches have been linked yet, indicating the need for prompt attention. The plugin version affected is up to 1.0.0, with no earlier versions specified. This vulnerability is particularly relevant to WooCommerce stores using the Local Shipping Labels plugin, which is used to generate and print shipping labels locally, a common requirement for small to medium e-commerce businesses.

For European organizations operating WooCommerce-based e-commerce sites using the Local Shipping Labels plugin, this vulnerability poses a significant risk. Successful exploitation could allow attackers to execute arbitrary JavaScript in the context of the victim's browser, leading to session hijacking, theft of sensitive customer data, or manipulation of order and shipping information. This can result in financial loss, reputational damage, and potential regulatory non-compliance under GDPR due to data breaches. Given the e-commerce sector's importance in Europe and the widespread use of WooCommerce, the vulnerability could affect a broad range of businesses, from SMEs to larger retailers. Additionally, the reflected XSS could be leveraged in targeted phishing campaigns against customers or employees, increasing the attack surface. The lack of authentication requirements lowers the barrier for exploitation, though user interaction is necessary, typically via clicking a malicious link. The changed scope indicates potential for broader impact beyond the plugin itself, possibly affecting other components or user sessions.

European organizations should immediately audit their WooCommerce installations to identify the presence of the NotFound Local Shipping Labels plugin, especially versions up to 1.0.0. Until an official patch is released, organizations should consider disabling or uninstalling the plugin to eliminate exposure. Web application firewalls (WAFs) should be configured to detect and block typical reflected XSS payloads targeting the affected plugin's endpoints. Input validation and output encoding should be enforced at the application level where possible, including sanitizing query parameters and form inputs related to shipping label generation. Security teams should educate users and administrators about the risks of clicking untrusted links, as exploitation requires user interaction. Monitoring web server logs for suspicious requests containing script tags or unusual parameters can help detect attempted exploitation. Once a patch is available, prompt application and testing of updates is critical. Additionally, implementing Content Security Policy (CSP) headers can help mitigate the impact of XSS by restricting script execution sources.