CVE-2018-20772 in Frog
Summary
by MITRE
Frog CMS 0.9.5 allows PHP code execution via <?php to the admin/?/layout/edit/1 URI.
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Analysis
by VulDB Data Team • 07/09/2023
CVE-2018-20772 represents a critical remote code execution vulnerability affecting Frog CMS version 0.9.5 that enables attackers to execute arbitrary PHP code through a specific administrative endpoint. This vulnerability resides within the layout editing functionality of the content management system, specifically at the URI path admin/?/layout/edit/1 where the application fails to properly validate or sanitize user-supplied input. The flaw allows malicious actors to inject PHP code directly into the system through the administrative interface, bypassing normal security controls and authentication mechanisms. The vulnerability stems from insufficient input validation and improper sanitization of data submitted through the layout editing form, creating a path for attackers to escalate privileges and gain full control over the affected system.
The technical exploitation of this vulnerability follows a well-defined attack pattern that aligns with CWE-94, which describes improper validation of dangerous or unexpected input leading to code execution. Attackers can leverage this weakness by crafting malicious PHP payloads within the layout editing interface, where the system processes the input without adequate security checks. The vulnerability's impact is particularly severe because it targets the administrative functionality of the CMS, which typically operates with elevated privileges and full system access. This allows attackers to not only execute arbitrary code but also potentially access sensitive data, modify content, and establish persistent backdoors within the system. The attack vector is relatively straightforward as it requires only access to the administrative interface, which may be protected by weak authentication or accessible through social engineering techniques.
The operational consequences of CVE-2018-20772 extend far beyond simple code execution, as it represents a complete compromise of the affected web application and underlying infrastructure. Organizations running Frog CMS 0.9.5 become vulnerable to full system takeover, data exfiltration, and potential lateral movement within their network. The vulnerability affects the core CMS functionality and can be exploited by attackers at the application layer without requiring system-level privileges or complex attack chains. This makes it particularly dangerous in environments where CMS systems are deployed without proper network segmentation or additional security controls. The attack aligns with ATT&CK technique T1059.007, which covers the use of PHP for command execution, and T1078.004, which addresses legitimate accounts used for persistence. The vulnerability's exploitation can result in complete data breaches, service disruption, and compliance violations, especially in regulated environments where CMS systems handle sensitive information.
Mitigation strategies for CVE-2018-20772 must address both immediate remediation and long-term security improvements to prevent similar vulnerabilities from emerging. The primary recommendation involves upgrading to a patched version of Frog CMS, as the vulnerability has been resolved in subsequent releases through proper input validation and sanitization measures. Organizations should implement strict access controls for administrative interfaces, including multi-factor authentication, IP whitelisting, and regular credential rotation. Network segmentation should be employed to isolate CMS systems from critical infrastructure, and web application firewalls should be configured to monitor for suspicious payloads. Additionally, security monitoring should include detection of unusual administrative activities and unauthorized code modifications. Regular security assessments and penetration testing should be conducted to identify similar vulnerabilities in other applications and systems. The vulnerability serves as a reminder of the critical importance of input validation and the principle of least privilege in web application security, aligning with security frameworks such as OWASP Top Ten and NIST cybersecurity guidelines. Organizations should also implement automated patch management processes to ensure timely deployment of security updates and maintain comprehensive incident response procedures to address potential exploitation attempts.