CVE-2026-90988 in Request a Quote Plugin
Summary
by MITRE • 10/02/2026
The Request a Quote WordPress plugin through 2.5.6 does not perform an authorization check on one of its unauthenticated AJAX handlers, allowing unauthenticated users to read the contact records of quote-request submissions, including records the site has not published.
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Analysis
by VulDB Data Team • 10/02/2026
The vulnerability identified in the Request a Quote WordPress plugin versions up to 2.5.6 represents a critical failure in access control mechanisms within the application's AJAX handler architecture. Specifically, the flaw resides in an unauthenticated endpoint that is designed to process requests for quote-related data without verifying whether the initiating user possesses valid administrative privileges or any other form of authorization. In secure web applications, particularly those handling sensitive business information like customer contact details and submission records, every action that modifies or retrieves stateful data must be preceded by a rigorous verification of the user's identity and permissions. The absence of this check allows any external actor to interact with the backend logic as if they were an authorized administrator, bypassing standard security boundaries entirely.
From a technical perspective, this issue classifies under CWE-862, which denotes Missing Authorization, and aligns with MITRE ATT&CK technique T1078, Valid Accounts, although in this case, no valid account is required at all due to the lack of authentication checks on specific endpoints. The attacker can exploit this by crafting malicious AJAX requests directed at the vulnerable endpoint. Since WordPress plugins often expose functionality through REST API or custom AJAX handlers registered via hooks such as wp_ajax_nopriv_*, developers must explicitly ensure that these public-facing interfaces do not perform privileged operations without additional safeguards like nonce verification and capability checks. The failure to implement these controls means that the server processes requests from anonymous users with elevated privileges, leading to a complete breakdown of the intended security model.
The operational impact of this vulnerability is severe due to the nature of the data exposed. Quote-request submissions typically contain personally identifiable information (PII) such as names, email addresses, phone numbers, and potentially company details provided by prospective clients. Because the flaw allows access to records that have not been published on the public-facing site, it exposes internal business intelligence and private customer interactions that were never intended for external visibility. This constitutes a significant data breach under regulations like GDPR or CCPA, as sensitive personal data is leaked without consent. Furthermore, this information can be aggregated by attackers to facilitate targeted phishing campaigns, social engineering attacks, or spamming activities against the exposed contacts, thereby extending the impact beyond mere privacy violation into active exploitation of the compromised user base.
Mitigation strategies must address both immediate remediation and long-term architectural improvements. The primary solution is for plugin developers to release an updated version that implements proper authorization checks on all AJAX handlers, ensuring that only users with specific capabilities, such as manage_options or edit_posts depending on context, can access these endpoints. For site administrators unable to update immediately, manual intervention involves disabling the vulnerable functionality if possible through configuration settings or removing the associated script handles from the page load sequence. Additionally, implementing a Web Application Firewall (WAF) rule that restricts AJAX requests to authenticated sessions with valid nonces can provide an effective layer of defense against exploitation attempts while patches are being deployed. Regular security audits and adherence to secure coding standards like OWASP Top 10 guidelines regarding broken access control are essential to prevent similar vulnerabilities in future development cycles.