CVE-2015-20115 Overview
CVE-2015-20115 is a Stored Cross-Site Scripting (XSS) vulnerability affecting Next Click Ventures RealtyScript version 4.0.2. The application fails to properly sanitize file uploads, allowing attackers to store malicious scripts through the file POST parameter in admin/tools.php. When uploaded files containing JavaScript code are accessed by other users, the malicious scripts execute in the context of the admin tools page, potentially compromising administrative sessions.
Critical Impact
Authenticated attackers can upload files containing malicious JavaScript that executes when accessed by administrators, potentially leading to session hijacking, credential theft, or administrative account compromise.
Affected Products
- Next Click Ventures RealtyScript 4.0.2
- RealtyScript Admin Tools Module (admin/tools.php)
Discovery Timeline
- 2026-03-16 - CVE CVE-2015-20115 published to NVD
- 2026-03-19 - Last updated in NVD database
Technical Details for CVE-2015-20115
Vulnerability Analysis
This vulnerability stems from insufficient input validation and output encoding in the file upload functionality within the RealtyScript administrative tools interface. The admin/tools.php endpoint processes file uploads via POST requests but fails to implement proper sanitization of the uploaded file contents. This allows an attacker with low-level privileges to upload files containing JavaScript payloads that are subsequently rendered without proper escaping when the uploaded content is accessed.
The vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation), specifically a Stored XSS variant. Unlike reflected XSS attacks, the malicious payload persists on the server and executes each time a victim accesses the affected page, making it particularly dangerous in multi-user administrative environments.
Root Cause
The root cause of this vulnerability is the absence of proper input validation and output encoding in the file upload handler. The file POST parameter in admin/tools.php accepts user-controlled input without sanitizing dangerous content such as <script> tags, event handlers, or other JavaScript execution vectors. The application stores these payloads and later renders them directly in the browser context without HTML entity encoding or Content Security Policy protections.
Attack Vector
The attack is network-based and requires authenticated access to the RealtyScript administrative interface. An attacker with valid credentials can exploit this vulnerability by submitting a specially crafted POST request to admin/tools.php containing JavaScript code within the file parameter. Once uploaded, any administrator or user viewing the affected administrative page will have the malicious script execute in their browser session. This can lead to session cookie theft, keylogging, administrative action execution on behalf of the victim, or further compromise of the system.
The vulnerability requires user interaction since a victim must navigate to the page containing the stored payload for the attack to succeed. For detailed technical information and proof-of-concept details, refer to the Zero Science Vulnerability ZSL-2015-5269 advisory and the Exploit-DB #38496 entry.
Detection Methods for CVE-2015-20115
Indicators of Compromise
- Unusual file uploads to admin/tools.php containing script tags, event handlers, or encoded JavaScript
- POST requests to admin/tools.php with the file parameter containing HTML special characters like <, >, or script
- Unexpected JavaScript execution errors or console warnings when administrators access the tools page
- Session token theft indicators such as outbound requests to external domains from the admin context
Detection Strategies
- Monitor web server access logs for POST requests to admin/tools.php with suspicious payloads in the file parameter
- Implement Web Application Firewall (WAF) rules to detect and block common XSS patterns in file upload parameters
- Deploy endpoint detection solutions to identify anomalous browser behavior or unexpected script execution in administrative sessions
- Review uploaded files for JavaScript content, encoded payloads, or HTML injection patterns
Monitoring Recommendations
- Enable detailed logging for all administrative actions in RealtyScript, particularly file upload operations
- Configure alerting for multiple failed or suspicious file upload attempts from the same session
- Monitor for signs of session hijacking such as administrative sessions from unexpected IP addresses or user agents
- Implement Content Security Policy (CSP) headers and monitor for CSP violation reports indicating attempted XSS exploitation
How to Mitigate CVE-2015-20115
Immediate Actions Required
- Restrict access to admin/tools.php to only trusted administrators until a patch is applied
- Implement Web Application Firewall rules to filter malicious input in the file upload parameter
- Review recently uploaded files for any malicious JavaScript content and remove suspicious entries
- Consider disabling the file upload functionality in admin tools if not business-critical
Patch Information
No official patch information is available from Next Click Ventures at this time. Organizations should contact the vendor directly for security updates or consider implementing the workarounds below. Additional technical details are available in the VulnCheck Advisory.
Workarounds
- Implement server-side input validation to strip or encode HTML and JavaScript content from file uploads
- Add Content Security Policy headers to prevent inline script execution: Content-Security-Policy: default-src 'self'; script-src 'self'
- Apply output encoding (HTML entity encoding) when rendering any user-supplied content in the admin interface
- Restrict file upload types to specific safe extensions and validate file content server-side
# Example Apache configuration to add CSP headers
<IfModule mod_headers.c>
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'"
Header set X-XSS-Protection "1; mode=block"
Header set X-Content-Type-Options "nosniff"
</IfModule>
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
