CVE-2017-15948 in Content Management System
Summary
by MITRE
Perch Content Management System 3.0.3 allows unrestricted file upload (with resultant XSS) via the Asset Title field in conjunction with the Select File field. This is exploitable with a Limited Admin account.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 01/16/2026
The vulnerability identified as CVE-2017-15948 affects Perch Content Management System version 3.0.3 and represents a critical security flaw that enables unauthorized file uploads with cross-site scripting capabilities. This vulnerability specifically targets the asset management functionality within the CMS, where attackers can manipulate the Asset Title field in combination with the Select File field to bypass normal upload restrictions. The flaw is particularly concerning because it can be exploited by users with limited administrative privileges, significantly expanding the potential attack surface beyond what might be expected from a standard user account.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the file upload mechanism. When users interact with the Asset Title field and subsequently select a file through the Select File interface, the system fails to properly validate the file type or content before processing the upload request. This weakness creates a pathway for malicious actors to upload files containing malicious javascript code or other harmful content that can be executed when the uploaded assets are accessed or displayed within the CMS interface. The vulnerability falls under CWE-434 which specifically addresses unrestricted upload of files with dangerous types, making it a well-documented pattern of insecure file handling practices.
From an operational perspective, this vulnerability presents a significant risk to organizations using Perch CMS as it allows attackers with limited admin access to potentially compromise the entire system. The combination of unrestricted file upload capability with cross-site scripting functionality means that attackers can not only upload malicious files but also execute arbitrary code within the context of other users' browsers. This creates a persistent threat vector that can be used for session hijacking, data exfiltration, or further escalation of privileges within the compromised environment. The vulnerability is particularly dangerous in multi-user CMS environments where different levels of access are granted to various team members.
The attack vector requires minimal privileges to exploit, as the vulnerability can be leveraged by users with limited administrative rights rather than requiring full administrative access. This characteristic significantly increases the risk profile since many organizations grant limited admin privileges to content editors or contributors who may not be fully trusted. The exploitation process involves crafting a malicious file with a valid extension but containing malicious code, then uploading it through the vulnerable interface. The resulting XSS payload can be triggered when the asset is viewed, potentially affecting other users who access the compromised content. Organizations should consider this vulnerability in relation to ATT&CK technique T1059.007 which covers command and scripting interpreter for execution, as the malicious code can be designed to establish persistent access or exfiltrate data. Mitigation strategies should include immediate patching of the CMS to address the file upload validation issues, implementing additional access controls to limit file upload capabilities, and conducting thorough security reviews of all file handling mechanisms within the content management system. Regular security audits and input validation testing should be implemented to prevent similar vulnerabilities from being introduced in future versions or custom implementations.