CVE-2024-11903 is a stored cross-site scripting (XSS) vulnerability identified in the WP eCards plugin for WordPress, affecting all versions up to and including 1.3.904. The vulnerability stems from improper neutralization of input during web page generation (CWE-79), specifically within the plugin's 'ecard' shortcode. The plugin fails to adequately sanitize and escape user-supplied attributes, allowing authenticated users with contributor-level permissions or higher to inject arbitrary JavaScript code into pages. When other users access these pages, the injected scripts execute in their browsers, potentially compromising session tokens, cookies, or enabling further attacks such as privilege escalation or defacement. The vulnerability requires no user interaction beyond visiting the compromised page but does require authenticated access, limiting exploitation to users with some level of trust within the WordPress site. The CVSS v3.1 base score is 6.4, reflecting a medium severity with network attack vector, low attack complexity, privileges required, no user interaction, and a scope change due to impact on other users. No public exploits have been reported yet, but the vulnerability poses a significant risk in multi-user WordPress environments where the plugin is installed. The lack of available patches at the time of publication necessitates immediate attention to mitigation strategies.

The primary impact of CVE-2024-11903 is the potential for attackers with contributor-level access to inject persistent malicious scripts into WordPress pages, which execute in the context of other users visiting those pages. This can lead to session hijacking, theft of sensitive information, unauthorized actions performed on behalf of other users, and potential privilege escalation if administrative users are targeted. The vulnerability undermines the integrity and confidentiality of the affected WordPress sites. Since the attack vector is network-based and does not require user interaction, the risk of widespread exploitation in environments with multiple contributors is significant. Organizations relying on the WP eCards plugin in collaborative or multi-author settings face increased risk of internal threat actors or compromised contributor accounts being leveraged to exploit this vulnerability. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as proof-of-concept code could emerge. The vulnerability could also damage organizational reputation if exploited to deface websites or distribute malware.

To mitigate CVE-2024-11903, organizations should first check for any official patches or updates from the WP eCards plugin vendor and apply them promptly once available. In the absence of patches, administrators should restrict contributor-level access to trusted users only and review existing contributor accounts for suspicious activity. Implementing a Web Application Firewall (WAF) with rules to detect and block malicious script injections targeting the 'ecard' shortcode parameters can provide interim protection. Site administrators should also consider disabling or removing the WP eCards plugin if it is not essential to reduce the attack surface. Additionally, employing Content Security Policy (CSP) headers can help mitigate the impact of injected scripts by restricting script execution sources. Regular security audits and monitoring for unusual page content or user behavior can aid in early detection of exploitation attempts. Finally, educating contributors about secure input practices and the risks of XSS can reduce inadvertent introduction of malicious content.