CVE-2025-53300 is a Stored Cross-site Scripting (XSS) vulnerability classified under CWE-79, affecting the douglaskarr Podcast Feed Player Widget and Shortcode up to version 2.2.0. This vulnerability arises from improper neutralization of input during web page generation, allowing malicious scripts to be stored and executed in the context of users viewing the affected widget or shortcode. The vulnerability requires an attacker with at least low privileges (PR:L) and some user interaction (UI:R) to exploit. The attack vector is network-based (AV:N), meaning exploitation can be attempted remotely. The scope is changed (S:C), indicating that the vulnerability affects resources beyond the initially vulnerable component, potentially impacting the confidentiality, integrity, and availability of the broader system. The CVSS 3.1 base score is 6.5, reflecting a medium severity level. Exploitation could lead to partial compromise of user data confidentiality and integrity, as well as potential availability impacts through script-based attacks such as session hijacking, defacement, or malware delivery. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability is particularly relevant for websites or platforms using this podcast widget to display feeds, where user-generated or external input is rendered without proper sanitization or encoding, enabling attackers to inject malicious JavaScript payloads that persist and execute when other users access the affected pages.

For European organizations, the impact of this vulnerability can be significant, especially for media companies, content platforms, and any websites integrating the douglaskarr Podcast Feed Player Widget and Shortcode. Exploitation could lead to unauthorized access to user session tokens, theft of sensitive information, defacement of web content, or distribution of malware to visitors, undermining user trust and potentially violating GDPR requirements related to data protection and breach notification. The medium severity indicates a moderate risk, but the scope change and stored nature of the XSS increase the potential damage, as multiple users can be affected over time. Organizations relying on this widget for podcast content delivery may face reputational damage, legal consequences, and operational disruptions if attackers leverage this vulnerability to compromise their web presence or user data.

Specific mitigation steps include: 1) Immediate audit and sanitization of all inputs processed by the Podcast Feed Player Widget and Shortcode, ensuring proper encoding and escaping of user-supplied data before rendering in HTML contexts. 2) Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of potential XSS payloads. 3) Monitor and restrict user privileges to minimize the ability of low-privilege users to inject malicious content. 4) Conduct thorough code reviews and penetration testing focused on input validation and output encoding in the affected components. 5) Stay alert for official patches or updates from the vendor and apply them promptly once available. 6) Educate content managers and administrators on safe content handling practices to prevent inadvertent injection of malicious scripts. 7) Deploy web application firewalls (WAFs) with rules targeting common XSS attack patterns to provide an additional layer of defense.