CVE-2023-51310 in Car Park Booking System
Summary
by MITRE • 02/20/2025
A lack of rate limiting in the 'Forgot Password', 'Email Settings' feature of PHPJabbers Car Park Booking System v3.0 allows attackers to send an excessive amount of email for a legitimate user, leading to a possible Denial of Service (DoS) via a large amount of generated e-mail messages.
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Analysis
by VulDB Data Team • 03/07/2026
The vulnerability identified as CVE-2023-51310 resides within the PHPJabbers Car Park Booking System version 3.0, specifically targeting the 'Forgot Password' and 'Email Settings' functionality. This weakness represents a critical security flaw that enables malicious actors to exploit the system's absence of rate limiting controls. The vulnerability operates by allowing unauthorized users to repeatedly trigger email generation mechanisms without proper throttling, potentially overwhelming the system's email infrastructure and legitimate users' inboxes. The affected system lacks any form of request rate limiting or user session monitoring that would normally prevent excessive email delivery attempts.
The technical implementation of this vulnerability stems from the application's failure to enforce any form of access control or usage limits on email-related functions. When a user requests password recovery or attempts to modify email settings, the system generates and dispatches email notifications without implementing any mechanism to track or restrict the frequency of such requests. This absence of rate limiting creates an exploitable condition where an attacker can systematically send numerous email requests for the same or different legitimate user accounts. The flaw manifests as a lack of input validation and access control measures that would normally be implemented to prevent abuse of email functionality. According to CWE classification, this vulnerability maps to CWE-770, which addresses allocation of resources without limits or throttling, and CWE-307, which covers improper restriction of excessive number of repeated access attempts.
The operational impact of this vulnerability extends beyond simple denial of service, creating potential for broader security implications within the application ecosystem. An attacker can leverage this weakness to flood legitimate users with unwanted email notifications, potentially leading to email account compromise through spam detection mechanisms or user confusion. The system's inability to distinguish between legitimate and malicious requests creates a pathway for automated abuse that can overwhelm email servers and potentially exhaust bandwidth or storage resources. This vulnerability also creates conditions for social engineering attacks where users might be confused by excessive email notifications or inadvertently provide sensitive information through fraudulent email interactions. The attack vector aligns with ATT&CK technique T1499.004, which involves denial of service through resource exhaustion, and T1566.001, covering spearphishing with attachments, as the excessive email generation can overwhelm email filtering systems and user inboxes.
Mitigation strategies for this vulnerability require immediate implementation of rate limiting mechanisms and access control measures within the affected application. Organizations should deploy request throttling controls that limit the number of email requests per user account or IP address within a specified time window. The system should implement session tracking and user authentication verification to prevent unauthorized access to email functions. Additionally, administrators should configure logging and monitoring capabilities to detect unusual email activity patterns that may indicate exploitation attempts. The solution should include automated alerting systems that notify administrators when email request volumes exceed normal thresholds, allowing for rapid response to potential abuse. Implementation of CAPTCHA mechanisms or other user verification controls can further prevent automated exploitation of this vulnerability. The fix should also incorporate proper error handling and user feedback mechanisms that provide appropriate responses without revealing system information that could aid attackers.