CVE-2024-9896 in BBP Core Plugin
Summary
by MITRE • 11/02/2024
The BBP Core – Expand bbPress powered forums with useful features plugin for WordPress is vulnerable to Reflected Cross-Site Scripting due to the use of add_query_arg without appropriate escaping on the URL in all versions up to, and including, 1.2.5. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
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Analysis
by VulDB Data Team • 03/01/2025
The vulnerability identified as CVE-2024-9896 affects the BBP Core plugin for WordPress, specifically targeting versions up to and including 1.2.5. This plugin extends bbPress forums with additional functionality, making it a common component in WordPress environments that rely on forum capabilities. The vulnerability stems from improper handling of URL parameters within the plugin's codebase, creating a pathway for malicious actors to exploit reflected cross-site scripting flaws. The issue is particularly concerning as it affects unauthenticated attackers who can leverage this weakness without requiring any prior access credentials or privileges.
The technical flaw manifests in the plugin's use of the add_query_arg function without implementing proper escaping mechanisms for URL parameters. This function is designed to add query arguments to URLs but fails to sanitize the input values before incorporating them into the final URL structure. When user-supplied input is processed through this function and subsequently rendered in web pages without adequate escaping, it creates an environment where malicious scripts can be injected and executed. The vulnerability is classified as reflected XSS because the malicious script is reflected off the web server and delivered to the victim's browser, making it particularly dangerous in web applications where user input is processed and displayed.
The operational impact of this vulnerability extends beyond simple script injection, as it allows attackers to execute arbitrary code within the context of a victim's browser session. An attacker could craft malicious URLs containing script payloads that, when clicked by an unsuspecting user, would execute in the user's browser. This could lead to session hijacking, credential theft, defacement of forum content, or redirection to malicious sites. The reflected nature of the vulnerability means that the attack vector is typically delivered through phishing emails, malicious links in forums, or social engineering campaigns designed to entice users into clicking compromised URLs. The vulnerability affects all users of the affected plugin version regardless of their authentication status, making it a critical concern for WordPress administrators managing forum-based websites.
Mitigation strategies for this vulnerability should prioritize immediate plugin updates to versions that address the XSS flaw. Administrators should also implement proper input validation and output escaping mechanisms throughout their WordPress installations, particularly for user-supplied parameters. The use of Content Security Policy headers can provide additional protection against script injection attacks by restricting the sources from which scripts can be loaded. Security monitoring should be enhanced to detect suspicious URL patterns and potential exploitation attempts. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and maps to ATT&CK technique T1566 related to social engineering and malicious link delivery. Organizations should conduct comprehensive security assessments of their WordPress environments to identify other plugins or themes that may be susceptible to similar vulnerabilities, as the improper use of URL handling functions is a common pattern in web application security flaws.