CVE-2015-8562 in Joomla
Summary
by MITRE
Joomla! 1.5.x, 2.x, and 3.x before 3.4.6 allow remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via the HTTP User-Agent header, as exploited in the wild in December 2015.
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Analysis
by VulDB Data Team • 11/08/2024
The vulnerability identified as CVE-2015-8562 represents a critical security flaw in Joomla! content management systems affecting versions 1.5.x, 2.x, and 3.x prior to 3.4.6. This vulnerability enables remote attackers to perform PHP object injection attacks through manipulation of the HTTP User-Agent header, creating a significant vector for arbitrary code execution. The flaw was actively exploited in the wild during December 2015, demonstrating its real-world impact and the urgency required for remediation.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within Joomla handles user agent data during authentication and session management processes, making it particularly dangerous as it can be exploited without requiring authentication or specific user interaction.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise. Attackers can leverage this vulnerability to gain unauthorized access to web servers, install backdoors, steal sensitive data, modify website content, or use the compromised system as a launching point for further attacks within the network. The widespread adoption of Joomla! across various organizations and websites means that exploitation could affect numerous systems simultaneously, potentially leading to large-scale data breaches and service disruptions.
Security practitioners should implement immediate mitigation strategies including updating to Joomla! version 3.4.6 or later, which contains patches addressing the object injection vulnerability. Organizations should also deploy web application firewalls to monitor and block suspicious User-Agent patterns, implement proper input validation at all entry points, and conduct regular security assessments of their web applications. This vulnerability aligns with CWE-502, which categorizes deserialization of untrusted data as a significant security risk, and maps to ATT&CK technique T1059.007 for PHP code execution, emphasizing the need for comprehensive defense-in-depth strategies to protect against similar injection attacks.