CVE-2024-3815 is a stored cross-site scripting (XSS) vulnerability identified in the Newspaper - News & WooCommerce WordPress theme, affecting all versions up to and including 12.6.5. The root cause is insufficient sanitization and escaping of user-supplied attachment metadata displayed on archive pages. This flaw allows authenticated users with author-level or higher privileges to inject arbitrary JavaScript code into pages. When other users access these pages, the malicious scripts execute in their browsers, potentially leading to session hijacking, defacement, or unauthorized actions performed with the victim's privileges. The vulnerability is classified under CWE-79, highlighting improper neutralization of input during web page generation. The CVSS v3.1 score of 5.5 reflects a medium severity, with an attack vector over the network, low complexity, requiring high privileges, no user interaction, and a scope change due to affecting other users. No public exploits have been reported yet, but the vulnerability poses a risk to websites using this theme, particularly those with multiple authors or contributors. The lack of patches at the time of reporting necessitates immediate mitigation steps to prevent exploitation.

The primary impact of this vulnerability is the potential compromise of confidentiality and integrity for users visiting affected pages. Attackers with author-level access can inject malicious scripts that execute in the browsers of other users, potentially stealing session cookies, performing unauthorized actions on behalf of users, or manipulating displayed content. This can lead to account takeover, data leakage, or reputational damage for affected organizations. Since the vulnerability requires authenticated access, the risk is somewhat mitigated but remains significant in multi-author environments such as news sites or e-commerce stores using the Newspaper theme. The scope change means that the attacker’s control extends beyond their own account to other users, increasing the threat surface. Although availability is not directly impacted, the indirect effects of exploitation could disrupt normal operations or user trust.

Organizations should immediately verify if they are using the Newspaper WordPress theme version 12.6.5 or earlier and plan to upgrade to a patched version once available. Until a patch is released, administrators should restrict author-level access to trusted users only and review existing author accounts for suspicious activity. Implementing Web Application Firewall (WAF) rules to detect and block suspicious script injection patterns in attachment metadata can provide temporary protection. Additionally, site administrators should enforce strict input validation and output encoding on all user-supplied data, especially metadata fields displayed on archive pages. Regular security audits and monitoring for unusual user behavior or injected scripts are recommended. Backup procedures should be verified to enable quick restoration if exploitation occurs. Finally, educating content authors about safe content practices and the risks of injecting untrusted data can reduce accidental exploitation.