CVE-2020-19046 in S-CMS
Summary
by MITRE • 08/31/2021
Cross Site Scripting (XSS) in S-CMS v1.0 allows remote attackers to execute arbitrary code via the component '/admin/tpl.php?page='.
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Analysis
by VulDB Data Team • 09/03/2021
The vulnerability identified as CVE-2020-19046 represents a critical cross site scripting flaw within S-CMS version 1.0 that exposes the system to remote code execution attacks through a specifically targeted component. This vulnerability resides in the administrative template handler at the path '/admin/tpl.php?page=' which fails to properly sanitize user input parameters, creating an exploitable entry point for malicious actors. The flaw allows remote attackers to inject malicious scripts into web pages viewed by other users, potentially leading to session hijacking, data theft, or complete system compromise. The vulnerability is classified under CWE-79 as a failure to sanitize user input, specifically manifesting as a cross site scripting vulnerability that can be leveraged for more severe attacks.
The technical implementation of this vulnerability stems from inadequate input validation and output encoding within the S-CMS administrative interface. When the system processes the page parameter through the tpl.php component, it does not properly escape or filter user-supplied data before rendering it in the web interface. This omission creates a persistent cross site scripting vector where attackers can inject malicious javascript payloads that execute in the context of other users' browsers. The attack surface is particularly dangerous because it targets the administrative component, potentially allowing attackers to gain elevated privileges and execute arbitrary code within the system's administrative context. This vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter usage, as successful exploitation could enable attackers to execute shell commands through the compromised administrative interface.
The operational impact of this vulnerability extends beyond simple script injection, as it provides attackers with the capability to establish persistent access to the administrative system. Once exploited, attackers can manipulate the content management system to redirect users to malicious sites, steal session cookies, or inject backdoors for continued access. The vulnerability's severity is amplified by the fact that it affects the administrative template system, which typically operates with elevated privileges and access to sensitive system functions. Organizations using S-CMS v1.0 are particularly at risk since this flaw could enable complete system compromise without requiring authentication for the initial exploit. The vulnerability's persistence is enhanced by the fact that malicious scripts injected through this vector can remain active until the system is patched or the affected component is manually cleaned.
Mitigation strategies for CVE-2020-19046 should prioritize immediate patching of the S-CMS application to the latest version that addresses this specific vulnerability. System administrators should implement input validation and output encoding measures that prevent the injection of malicious scripts into the administrative template system. The implementation of Content Security Policy headers can provide additional protection against script execution, while regular security audits should verify that all user inputs are properly sanitized before processing. Organizations should also consider implementing web application firewalls to detect and block malicious requests targeting the vulnerable tpl.php component. Given the ATT&CK framework implications, security teams should monitor for signs of lateral movement or privilege escalation attempts that may indicate successful exploitation of this vulnerability. The remediation process should include thorough testing to ensure that the patch does not introduce regressions in legitimate administrative functionality while maintaining the security hardening measures that prevent similar vulnerabilities from occurring in other components of the system.