CVE-2023-0366 in Loan Comparison Plugin
Summary
by MITRE • 02/21/2023
The Loan Comparison WordPress plugin before 1.5.3 does not validate and escape some of its shortcode attributes before outputting them back in a page/post where the shortcode is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 03/23/2023
The CVE-2023-0366 vulnerability affects the Loan Comparison WordPress plugin version 1.5.2 and earlier, representing a critical stored cross-site scripting flaw that undermines web application security. This vulnerability specifically targets the plugin's handling of shortcode attributes, which are essential components for embedding dynamic content within WordPress pages and posts. The issue arises from insufficient input validation and output escaping mechanisms within the plugin's codebase, creating an attack vector that can be exploited by users possessing contributor-level privileges or higher.
The technical flaw manifests in how the plugin processes and renders shortcode attributes without proper sanitization procedures. When administrators or contributors embed loan comparison shortcodes within content, the plugin fails to validate or escape user-supplied parameters before incorporating them into the final HTML output. This omission allows malicious actors to inject arbitrary JavaScript code through carefully crafted shortcode attributes, which then executes in the browsers of unsuspecting visitors who view the affected pages. The vulnerability is classified as stored XSS because the malicious code is permanently stored within the WordPress database and persists until manually removed, making it particularly dangerous for long-term exposure.
From an operational perspective, this vulnerability poses significant risks to WordPress sites utilizing the Loan Comparison plugin, as it enables attackers to execute malicious scripts in the context of the victim's browser session. The impact extends beyond simple script execution, potentially allowing attackers to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious websites. The contributor role escalation aspect means that even less privileged users within the WordPress ecosystem can exploit this vulnerability, making it particularly concerning for sites with multiple content creators or contributors. The stored nature of the vulnerability also means that once exploited, the malicious code continues to affect visitors until the compromised content is manually cleaned, creating ongoing security exposure.
Security professionals should implement immediate mitigations including updating the Loan Comparison plugin to version 1.5.3 or later, which contains the necessary patches to address the validation and escaping issues. Additionally, administrators should conduct thorough audits of existing shortcode implementations to identify and remove any potentially compromised content. The vulnerability aligns with CWE-79 (Cross-Site Scripting) and follows patterns commonly associated with ATT&CK technique T1566.001 (Phishing via Social Media) and T1059.007 (Command and Scripting Interpreter: JavaScript), demonstrating how poorly validated user input can enable sophisticated attack vectors. Organizations should also consider implementing Content Security Policy (CSP) headers as an additional defense-in-depth measure to mitigate the impact of potential XSS attacks, though this does not replace proper input validation and sanitization within the application code itself.