CVE-2009-4099 in Com Gcalendar
Summary
by MITRE
SQL injection vulnerability in the Google Calendar GCalendar (com_gcalendar) component 1.1.2, 2.1.4, and possibly earlier versions for Joomla! allows remote attackers to execute arbitrary SQL commands via the gcid parameter. NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 06/15/2025
The CVE-2009-4099 vulnerability represents a critical sql injection flaw within the Google Calendar GCalendar component for Joomla websites that utilize this calendar component. The flaw specifically manifests through the gcid parameter, which serves as an entry point for malicious actors to inject arbitrary sql commands into the underlying database system. The vulnerability stems from inadequate input validation and sanitization mechanisms within the component's code implementation, allowing attackers to manipulate the sql query execution flow through crafted malicious input.
The technical exploitation of this vulnerability occurs when an attacker submits a specially crafted gcid parameter value that bypasses the application's normal input processing routines. This allows the attacker to inject malicious sql code that gets executed within the context of the database connection. The vulnerability aligns with CWE-89, which categorizes sql injection as a fundamental weakness in application security where untrusted data is incorporated into sql commands without proper sanitization or parameterization. The attack vector enables remote code execution capabilities, potentially allowing threat actors to extract sensitive data, modify database contents, or even escalate privileges within the affected system. This vulnerability is particularly dangerous because it affects widely used content management systems where the calendar component is commonly deployed.
From an operational impact perspective, this vulnerability creates substantial risk for organizations using affected Joomla! versions with the GCalendar component. Successful exploitation could result in complete database compromise, leading to data breaches, unauthorized access to user information, and potential system takeover. The vulnerability affects the confidentiality, integrity, and availability of the affected systems, as attackers can manipulate calendar data, access user credentials, or extract sensitive organizational information. Security analysts note that this vulnerability can be exploited through simple web browser interactions, making it particularly dangerous as it requires minimal technical expertise to exploit. The attack can be executed without authentication, allowing any remote user to potentially compromise the system.
Mitigation strategies for CVE-2009-4099 should prioritize immediate patching of affected Joomla! installations with the vendor-provided security updates. Organizations must implement proper input validation and parameterized queries to prevent similar vulnerabilities in their applications. The principle of least privilege should be enforced by ensuring database connections used by the calendar component have minimal required permissions. Additionally, web application firewalls and intrusion detection systems can help detect and block malicious sql injection attempts. Security teams should conduct thorough vulnerability assessments to identify all instances of the affected component across their infrastructure. The remediation process should include disabling or removing the vulnerable component if immediate patching is not feasible, while also implementing comprehensive monitoring to detect any exploitation attempts. This vulnerability highlights the critical importance of maintaining up-to-date security patches and following secure coding practices as outlined in the ATT&CK framework's application security categories, particularly focusing on preventing command injection attacks that leverage input validation weaknesses.