CVE-2017-11154 in Photo Station
Summary
by MITRE
Unrestricted file upload vulnerability in PixlrEditorHandler.php in Synology Photo Station before 6.7.3-3432 and 6.3-2967 allows remote attackers to create arbitrary PHP scripts via the type parameter.
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Analysis
by VulDB Data Team • 06/23/2024
The vulnerability CVE-2017-11154 represents a critical unrestricted file upload flaw in Synology Photo Station's PixlrEditorHandler.php component affecting versions prior to 6.7.3-3432 and 6.3-2967. This vulnerability stems from inadequate input validation and sanitization mechanisms within the file upload processing logic, allowing remote attackers to bypass security restrictions and upload malicious files to the target system. The vulnerability specifically manifests through the type parameter manipulation, which controls the file type handling during the upload process, creating a pathway for attackers to execute arbitrary PHP code on the affected server.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious file upload request that includes a specially crafted type parameter value. The flaw lies in the application's failure to properly validate or sanitize the file type information, enabling attackers to upload PHP scripts with extensions that would normally be restricted. This weakness maps directly to CWE-434, which describes unrestricted upload of code or files, and represents a classic path to remote code execution through file upload vulnerabilities. The vulnerability allows attackers to bypass normal file type restrictions and execute arbitrary PHP code, creating a persistent backdoor or enabling further attack vectors within the network.
From an operational impact perspective, this vulnerability provides attackers with a direct pathway to achieve remote code execution on the affected Synology Photo Station server. Once successfully exploited, attackers can upload malicious PHP scripts that execute with the privileges of the web server process, typically running as the www-data or similar user account. The implications extend beyond simple code execution, as attackers can leverage this capability to establish persistent access, escalate privileges, exfiltrate sensitive data, or use the compromised system as a launch point for further attacks within the network infrastructure. This vulnerability affects organizations that rely on Synology Photo Station for image management and sharing, potentially exposing sensitive corporate or personal data stored within these systems.
The mitigation strategy for CVE-2017-11154 requires immediate implementation of the vendor-provided security patches released in versions 6.7.3-3432 and 6.3-2967. Organizations should also implement additional defensive measures including strict file type validation, implementing proper content type checking, and deploying web application firewalls to monitor and block suspicious upload requests. Network segmentation and privilege separation should be enforced to limit the potential impact of successful exploitation. The vulnerability demonstrates the importance of proper input validation and the principle of least privilege in web application security, aligning with ATT&CK technique T1190 for exploitation of vulnerabilities and T1059 for execution through command and scripting interpreters. Regular security assessments and vulnerability scanning should be conducted to identify similar weaknesses in other applications and systems within the organization's attack surface.