CVE-2021-24946 in Modern Events Calendar Lite Plugin
Summary
by MITRE • 12/13/2021
The Modern Events Calendar Lite WordPress plugin before 6.1.5 does not sanitise and escape the time parameter before using it in a SQL statement in the mec_load_single_page AJAX action, available to unauthenticated users, leading to an unauthenticated SQL injection issue
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Analysis
by VulDB Data Team • 01/04/2025
The vulnerability identified as CVE-2021-24946 affects the Modern Events Calendar Lite WordPress plugin version 6.1.4 and earlier, representing a critical security flaw that exposes unauthenticated users to potential SQL injection attacks. This vulnerability exists within the plugin's AJAX handling mechanism where the time parameter is inadequately sanitized before being incorporated into database queries. The affected action mec_load_single_page operates without requiring user authentication, making the vulnerability accessible to any internet user who can interact with the WordPress site.
The technical implementation of this vulnerability stems from improper input validation and sanitization practices within the plugin's backend processing. When the mec_load_single_page AJAX action receives a time parameter, it fails to properly escape or sanitize this input before executing SQL queries against the WordPress database. This omission creates a direct pathway for malicious actors to inject arbitrary SQL commands through the time parameter, potentially allowing them to extract sensitive data, modify database contents, or execute unauthorized operations on the affected system. The vulnerability specifically manifests in the SQL statement construction where user-supplied time values are directly interpolated into query strings without adequate security measures.
The operational impact of this unauthenticated SQL injection vulnerability extends beyond simple data theft, potentially enabling attackers to escalate their privileges within the WordPress environment. An attacker could leverage this vulnerability to access administrative functions, modify event data, inject malicious code, or even establish persistent access to the compromised site. The implications are particularly severe given that the vulnerability affects a widely used calendar plugin, meaning that numerous WordPress installations could be at risk. This type of vulnerability aligns with CWE-89 which specifically addresses SQL injection flaws, and represents a clear violation of secure coding practices that should prevent user input from directly influencing database query construction. The attack vector is particularly dangerous because it requires no authentication credentials and can be exploited through standard web browser interactions.
Mitigation strategies for CVE-2021-24946 should prioritize immediate plugin updates to version 6.1.5 or later, which contain the necessary sanitization fixes. System administrators should also implement additional protective measures including input validation at the web application firewall level, monitoring for suspicious parameter patterns in AJAX requests, and implementing database query parameterization techniques. The vulnerability demonstrates the critical importance of proper input sanitization and the principle of least privilege in web application security. Organizations should also consider implementing database activity monitoring to detect unusual query patterns that might indicate exploitation attempts, as well as conducting comprehensive security assessments of all installed WordPress plugins to identify similar sanitization issues. This vulnerability serves as a reminder of the ATT&CK framework's relevance in understanding how initial access through unauthenticated SQL injection can lead to broader system compromise and data exfiltration operations.