CVE-2019-16722 in zzzphp
Summary
by MITRE
ZZZCMS zzzphp v1.7.2 has an insufficient protection mechanism against PHP Code Execution, because passthru bypasses an str_ireplace operation.
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Analysis
by VulDB Data Team • 12/27/2023
The vulnerability CVE-2019-16722 affects ZZZCMS zzzphp version 1.7.2 and represents a critical security flaw that undermines the application's code execution protections. This issue stems from an insufficient safeguard mechanism that allows malicious actors to bypass security measures designed to prevent unauthorized PHP code execution. The vulnerability specifically exploits a weakness in how the system handles input validation, creating a pathway for attackers to execute arbitrary PHP code within the target environment. The flaw occurs when the passthru function is used in conjunction with an str_ireplace operation, which should normally prevent code injection but fails to adequately address certain bypass techniques.
The technical implementation of this vulnerability demonstrates a failure in input sanitization and validation protocols within the CMS framework. When user input passes through the passthru function, the str_ireplace operation intended to filter out dangerous characters and sequences proves inadequate in preventing code execution. This creates a scenario where attackers can craft malicious input that circumvents the intended security controls, effectively allowing them to execute arbitrary PHP code on the server. The bypass mechanism exploits the interaction between these two functions, where the replacement operation does not sufficiently neutralize the dangerous input patterns that would normally be blocked.
From an operational impact perspective, this vulnerability poses significant risks to organizations using the affected CMS version. Successful exploitation enables attackers to gain full control over the web server, potentially leading to data breaches, system compromise, and complete loss of control over the affected application. The vulnerability can be exploited remotely without authentication, making it particularly dangerous as it requires no prior access to the system. Attackers can leverage this flaw to upload malware, steal sensitive data, modify content, or establish persistent backdoors within the compromised environment. The impact extends beyond immediate code execution to include potential lateral movement within networks and escalation of privileges.
Organizations should implement immediate mitigations including updating to the latest version of ZZZCMS zzzphp that addresses this vulnerability, applying the vendor-provided security patches, and implementing additional input validation measures. Network segmentation and monitoring should be enhanced to detect suspicious activities that may indicate exploitation attempts. The vulnerability aligns with CWE-74 and CWE-94 categories, representing code injection and improper neutralization of special elements used in OS commands, respectively. From an ATT&CK framework perspective, this vulnerability maps to T1059.007 for PHP and T1078 for valid accounts, as exploitation typically involves executing commands through legitimate PHP processes. Additional protective measures include implementing web application firewalls, restricting file upload capabilities, and conducting regular security audits to identify and remediate similar vulnerabilities in the application stack.