CVE-2023-43355 in CMS Made Simple
Summary
by MITRE • 10/25/2023
Cross Site Scripting vulnerability in CMSmadesimple v.2.2.18 allows a local attacker to execute arbitrary code via a crafted script to the password and password again parameters in the My Preferences - Add user component.
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Analysis
by VulDB Data Team • 02/05/2026
The vulnerability identified as CVE-2023-43355 represents a critical cross site scripting flaw within CMSmadesimple version 2.2.18 that enables local attackers to execute arbitrary code through manipulated input parameters. This vulnerability specifically targets the My Preferences - Add user component where the password and password again fields are susceptible to malicious script injection. The flaw arises from inadequate input validation and sanitization mechanisms that fail to properly filter or escape user-supplied data before processing. As a local attacker, the threat actor can leverage this weakness to inject malicious JavaScript code that will execute within the context of the victim's browser session, potentially leading to complete system compromise and unauthorized access to sensitive data.
The technical implementation of this vulnerability stems from the application's insufficient sanitization of user inputs in the password parameter fields. When a user attempts to add a new user account or modify their own preferences, the system accepts raw input without proper validation, allowing malicious payloads to be stored and subsequently executed. This represents a classic case of CWE-79 - Improper Neutralization of Input During Web Page Generation, where user-controllable data flows directly into web page content without adequate sanitization. The vulnerability is particularly dangerous because it operates within the administrative context of the CMS, providing attackers with elevated privileges and access to sensitive system functions.
The operational impact of CVE-2023-43355 extends beyond simple script execution to encompass full system compromise and data exfiltration capabilities. Attackers can leverage this vulnerability to establish persistent access, escalate privileges, and potentially move laterally within the network infrastructure. The local nature of the attack means that an attacker must already have some level of access to the system, but once exploited, the consequences can be devastating. The vulnerability can be exploited through various attack vectors including social engineering campaigns where administrators are tricked into submitting malicious input, or through compromised accounts that are then used to execute the exploit. This flaw directly maps to ATT&CK technique T1059.007 - Command and Scripting Interpreter: JavaScript, as it enables the execution of malicious javascript code within the target environment.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security hardening measures. The primary recommendation is to upgrade to a patched version of CMSmadesimple that resolves the input validation issues in the My Preferences component. Organizations should also implement comprehensive input validation and sanitization procedures that filter out potentially malicious content before processing user inputs. Additional protective measures include implementing proper access controls to limit local system access, deploying web application firewalls to detect and block malicious payloads, and establishing regular security auditing procedures to identify similar vulnerabilities. The implementation of CSP headers and proper output encoding can further reduce the impact of any remaining XSS vulnerabilities. Security teams should also conduct regular penetration testing and vulnerability assessments to ensure that similar flaws are not present in other components of the CMS platform or related systems.