CVE-2015-2781 in hotEx Billing Manager
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in cgi-bin/hotspotlogin.cgi in Hotspot Express hotEx Billing Manager 73 allows remote attackers to inject arbitrary web script or HTML via the reply parameter.
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Analysis
by VulDB Data Team • 05/06/2022
The vulnerability identified as CVE-2015-2781 represents a critical cross-site scripting flaw within the hotEx Billing Manager 73 software suite, specifically affecting the cgi-bin/hotspotlogin.cgi component. This issue resides in the Hotspot Express hotEx Billing Manager version 73, which is commonly deployed in wireless access point and hotspot management environments where user authentication and billing systems are critical components of network infrastructure. The vulnerability manifests through the reply parameter within the hotspotlogin.cgi script, creating an avenue for malicious actors to execute arbitrary web scripts or HTML code within the context of authenticated user sessions.
The technical exploitation of this vulnerability occurs through the improper sanitization of user input within the reply parameter, which is processed by the hotspotlogin.cgi script without adequate validation or encoding mechanisms. When a remote attacker crafts a malicious payload containing script tags or other HTML elements and submits it through the reply parameter, the application fails to properly escape or filter this input before rendering it within the web page context. This allows the injected code to execute in the victim's browser, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The vulnerability is classified as a classic reflected cross-site scripting issue where the malicious payload is reflected back to the user through the application's response.
The operational impact of this vulnerability extends beyond simple script injection, as it provides attackers with significant opportunities to compromise user sessions and potentially gain unauthorized access to the billing and authentication systems. In hotspot environments, this could enable attackers to steal user credentials, manipulate billing records, or redirect users to phishing sites that appear legitimate within the network's authentication framework. The vulnerability affects the authentication flow of the hotspot system, potentially allowing attackers to bypass authentication mechanisms or manipulate the login process itself. According to CWE standards, this corresponds to CWE-79 which specifically addresses Cross-site Scripting vulnerabilities, and aligns with ATT&CK technique T1566 which covers Phishing through social engineering.
Mitigation strategies for CVE-2015-2781 should focus on implementing proper input validation and output encoding mechanisms within the hotspotlogin.cgi script. The most effective immediate solution involves sanitizing all user inputs, particularly the reply parameter, through proper HTML entity encoding before rendering any user-supplied content within web pages. Additionally, implementing a Content Security Policy (CSP) header can provide an additional layer of protection against script execution. Organizations should also consider upgrading to patched versions of the hotEx Billing Manager software, as this vulnerability was likely addressed in subsequent releases. Network segmentation and monitoring for suspicious authentication traffic patterns can help detect exploitation attempts. The implementation of proper parameter validation and the removal of unnecessary script execution capabilities within the CGI script would fully remediate this vulnerability according to industry best practices for web application security.