CVE-2025-2167 is a stored Cross-Site Scripting (XSS) vulnerability identified in the bastho Event post plugin for WordPress, affecting all versions up to and including 5.9.9. The vulnerability stems from insufficient sanitization and escaping of user-supplied input within the 'events_list' shortcode attributes. Authenticated users with contributor-level access or higher can exploit this flaw by injecting arbitrary JavaScript code into event pages. Because the malicious script is stored persistently, it executes in the context of any user who views the compromised page, potentially leading to session hijacking, privilege escalation, or unauthorized actions on behalf of the victim. The attack vector requires no user interaction beyond page access and does not require elevated privileges beyond contributor-level authentication. The CVSS 3.1 base score of 5.4 reflects a medium severity, with network attack vector, low attack complexity, and no user interaction needed. Although no known exploits have been reported in the wild, the vulnerability poses a significant risk to websites that allow multiple contributors and display event information publicly. The root cause is the failure to properly neutralize input during web page generation, a classic CWE-79 issue. Mitigation requires patching the plugin once updates are available or applying strict input validation and output encoding on shortcode attributes. Monitoring for suspicious script injections and restricting contributor privileges can also reduce risk.

The impact of CVE-2025-2167 can be significant for organizations using the bastho Event post plugin on WordPress sites, especially those with multiple contributors or public-facing event pages. Successful exploitation allows attackers to inject persistent malicious scripts that execute in the browsers of site visitors, potentially leading to session hijacking, theft of sensitive information, unauthorized actions performed with the victim's privileges, or defacement of web content. This can undermine user trust, damage brand reputation, and expose organizations to regulatory and compliance risks related to data breaches. Since the vulnerability requires contributor-level authentication, insider threats or compromised contributor accounts increase risk. The vulnerability does not directly affect availability but compromises confidentiality and integrity. Organizations with high traffic or sensitive user data are at greater risk. Although no exploits are known in the wild, the ease of exploitation and common use of WordPress plugins make this a credible threat that could be leveraged in targeted or opportunistic attacks.

1. Immediately restrict contributor-level access to trusted users only and review existing contributor accounts for suspicious activity. 2. Monitor event pages for unexpected or suspicious script content and remove any unauthorized code. 3. Apply strict input validation and output encoding on all user-supplied shortcode attributes, either via plugin updates or custom code hooks. 4. Disable or remove the bastho Event post plugin if it is not essential to reduce attack surface. 5. Regularly update WordPress core and all plugins to the latest versions once a patch addressing this vulnerability is released. 6. Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on affected pages. 7. Educate contributors about the risks of injecting untrusted content and enforce secure content creation policies. 8. Use Web Application Firewalls (WAFs) with rules to detect and block common XSS payloads targeting shortcode parameters. 9. Conduct periodic security audits and penetration tests focusing on user input handling in WordPress plugins. 10. Backup website data regularly to enable quick recovery in case of compromise.