CVE-2019-1010062 in PluckCMS
Summary
by MITRE
PluckCMS 4.7.4 and earlier is affected by: CWE-434 Unrestricted Upload of File with Dangerous Type. The impact is: get webshell. The component is: data/inc/images.php line36. The attack vector is: modify the MIME TYPE on HTTP request to upload a php file. The fixed version is: after commit 09f0ab871bf633973cfd9fc4fe59d4a912397cf8.
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Analysis
by VulDB Data Team • 10/26/2023
The vulnerability identified as CVE-2019-1010062 affects PluckCMS versions 4.7.4 and earlier, representing a critical security flaw categorized under CWE-434 Unrestricted Upload of File with Dangerous Type. This weakness allows attackers to bypass file upload restrictions and execute arbitrary code on the target system. The vulnerability specifically resides in the data/inc/images.php file at line 36, where the application fails to properly validate file types during the upload process. The attack vector exploits the application's insufficient validation of MIME types, enabling malicious actors to manipulate HTTP requests and upload PHP files that can be executed as webshells. This particular flaw represents a significant risk to web application security as it directly enables remote code execution capabilities, allowing attackers to gain persistent access to the affected system.
The technical implementation of this vulnerability demonstrates a classic insecure file upload vulnerability where the application relies on client-side MIME type validation rather than comprehensive server-side verification. When an attacker modifies the MIME type in the HTTP request to appear as an image file while actually uploading a PHP script, the application accepts the upload without proper validation. This occurs because the system does not perform adequate checks on file extensions, MIME types, or file content to ensure that uploaded files match their claimed types. The vulnerability is particularly dangerous because it allows attackers to upload malicious PHP files that can execute arbitrary commands on the web server, potentially leading to complete system compromise. The specific location in data/inc/images.php at line 36 indicates that the application uses a simple file validation approach that can be easily bypassed through request manipulation.
The operational impact of this vulnerability extends beyond simple code execution to encompass full system compromise and persistent access capabilities. Once an attacker successfully uploads a webshell through this vulnerability, they can execute commands on the target server with the privileges of the web application user. This provides attackers with the ability to access sensitive data, modify website content, establish backdoors, and potentially escalate privileges to gain administrative access to the entire system. The vulnerability also enables attackers to use the compromised system as a pivot point for attacking other systems within the network. The implications are severe as it allows for data exfiltration, system reconnaissance, and long-term persistence without detection. Organizations using affected versions of PluckCMS face significant risk of unauthorized access, data breaches, and potential regulatory compliance violations.
The fix for this vulnerability was implemented through commit 09f0ab871bf633973cfd9fc4fe59d4a912397cf8, which addresses the root cause by implementing proper file type validation mechanisms. The recommended mitigation strategy involves implementing comprehensive file validation that checks not only file extensions but also file content signatures and MIME types using server-side validation. Organizations should implement multiple layers of protection including whitelist-based file type validation, content-based file analysis, and proper file permissions to prevent execution of uploaded files. Additionally, the fix should include proper error handling and logging to detect and respond to suspicious upload attempts. Security practices should follow ATT&CK framework recommendations for defensive measures against file upload vulnerabilities, including network segmentation, application firewalls, and regular security assessments to prevent similar vulnerabilities from being introduced in future versions. The remediation process should also include comprehensive testing to ensure that the file upload functionality works correctly while maintaining security controls.