CVE-2023-51293 in Event Booking Calendar
Summary
by MITRE • 02/19/2025
A lack of rate limiting in the 'Forgot Password', 'Email Settings' feature of PHPJabbers Event Booking Calendar v4.0 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 • 02/20/2025
The vulnerability identified as CVE-2023-51293 resides within the PHPJabbers Event Booking Calendar version 4.0, specifically targeting the 'Forgot Password' and 'Email Settings' functionality. This issue represents a critical security flaw that directly impacts the system's ability to manage email communication effectively. The absence of proper rate limiting mechanisms in these features creates an exploitable condition that allows malicious actors to generate an excessive volume of email messages targeting legitimate user accounts. The vulnerability operates by leveraging the legitimate email sending capabilities of the application without adequate restrictions on the frequency or volume of messages that can be dispatched through these specific interfaces.
From a technical perspective, this vulnerability manifests as a failure to implement rate limiting controls within the application's email handling processes. The affected components are designed to send password reset emails and manage email settings notifications without any mechanism to track or restrict the number of messages sent within a given time period. This architectural oversight enables attackers to repeatedly trigger email generation functions, potentially exhausting system resources and network bandwidth while overwhelming legitimate user inboxes. The flaw falls under the category of insufficient rate limiting as defined by CWE-307, which specifically addresses improper restriction of repeated access attempts to protected resources. The vulnerability directly enables a denial of service condition by consuming excessive system resources through email generation and delivery processes.
The operational impact of this vulnerability extends beyond simple email flooding to encompass broader system availability concerns and potential resource exhaustion. Attackers can exploit this weakness to overwhelm the mail server infrastructure, consume bandwidth, and potentially cause legitimate users to miss important notifications due to inbox saturation. The DoS condition can be particularly damaging in environments where the application serves as a critical communication channel for event management and user engagement. Network administrators may observe unusual traffic patterns and increased email server load, while legitimate users face potential disruption to their email services and communication workflows. This vulnerability also creates opportunities for secondary attacks, as excessive email generation can mask other malicious activities or contribute to spam filtering issues that affect overall system security posture.
Mitigation strategies for CVE-2023-51293 should focus on implementing robust rate limiting mechanisms within the affected application features. Organizations should deploy time-based rate limiting controls that restrict the number of password reset requests and email setting modifications per user account within specific time windows. The implementation should include tracking mechanisms to monitor access patterns and automatically block suspicious activity. Network-level controls can supplement application-level protections by implementing email rate limiting at the infrastructure level. Security teams should also consider implementing account lockout mechanisms after excessive failed attempts and monitoring for unusual email generation patterns. The solution aligns with ATT&CK technique T1499.004 for denial of service attacks, where adversaries leverage application weaknesses to consume system resources and disrupt legitimate service delivery. Additionally, this vulnerability demonstrates the importance of following security best practices outlined in OWASP Top Ten and NIST cybersecurity frameworks for preventing and mitigating application-level attacks through proper access controls and resource management.