CVE-2017-14347 in NexusPHP
Summary
by MITRE
NexusPHP 1.5.beta5.20120707 has XSS in the returnto parameter to fun.php in a delete action.
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Analysis
by VulDB Data Team • 11/15/2019
The vulnerability identified as CVE-2017-14347 resides within NexusPHP version 1.5.beta5.20120707, specifically targeting the fun.php script's handling of the returnto parameter during delete operations. This represents a classic cross-site scripting flaw that allows malicious actors to inject arbitrary JavaScript code into the application's response. The vulnerability manifests when the application fails to properly sanitize or encode user-supplied input before incorporating it into dynamic web content, creating an avenue for attackers to execute malicious scripts in the context of authenticated users' browsers.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding practices within the NexusPHP application framework. When a user performs a delete action and the returnto parameter is processed, the application directly incorporates this parameter value into the page response without adequate sanitization. This flaw falls under CWE-79 which specifically addresses Cross-Site Scripting vulnerabilities, where improper validation of input data allows attackers to inject malicious scripts that execute in the victim's browser context. The vulnerability is particularly concerning because it occurs during authenticated operations, potentially allowing attackers to escalate privileges or perform unauthorized actions on behalf of legitimate users.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attack vectors including session hijacking, credential theft, and data exfiltration. An attacker could craft a malicious URL containing a returnto parameter with embedded JavaScript that, when clicked by an authenticated user, would execute commands in their browser context. This could lead to unauthorized access to sensitive user data, modification of content, or redirection to malicious sites. The vulnerability is particularly dangerous in environments where users have elevated privileges or access to sensitive information, as it could facilitate privilege escalation attacks and persistent security breaches.
Mitigation strategies for CVE-2017-14347 should focus on implementing robust input validation and output encoding mechanisms throughout the application. The primary remediation involves sanitizing all user-supplied input parameters, particularly those used in dynamic content generation, through proper encoding techniques such as HTML entity encoding or context-appropriate escaping. Organizations should also implement Content Security Policy headers to limit script execution and prevent unauthorized code injection. Additionally, regular security code reviews and automated vulnerability scanning should be integrated into the development lifecycle to identify similar issues before they can be exploited. This vulnerability aligns with ATT&CK technique T1059 which covers command and scripting interpreter usage, and T1566 which addresses credential access through social engineering, highlighting the potential for this flaw to serve as a launching point for broader attack campaigns.