CVE-2026-51025 in fuint Member Marketing System
Summary
by MITRE • 07/21/2026
Cross Site Scripting vulnerability in fuint Member Marketing System <=v1.0 allows a remote attacker to execute arbitrary code via the ClientMessageController.java file
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Analysis
by VulDB Data Team • 07/21/2026
This cross site scripting vulnerability exists within the fuint Member Marketing System version 1.0 and earlier, representing a critical security flaw that enables remote code execution through improper input validation in the ClientMessageController.java file. The vulnerability stems from insufficient sanitization of user-supplied data that flows directly into web responses without proper encoding or validation mechanisms. Attackers can exploit this weakness by injecting malicious javascript payloads through client message parameters, which are then executed in the context of other users' browsers when they view affected pages.
The technical implementation of this flaw involves the ClientMessageController.java file failing to properly escape or filter user input before rendering it within web responses. This creates an environment where malicious scripts can be injected and subsequently executed in victim browsers, potentially leading to session hijacking, data theft, or further compromise of the affected system. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications. From an operational perspective this weakness represents a significant risk as it allows attackers to escalate privileges and gain unauthorized access to user sessions, potentially leading to complete system compromise.
The impact of this vulnerability extends beyond simple script execution as it provides attackers with a foothold for more sophisticated attacks including credential theft, data exfiltration, and persistent backdoor establishment. The remote nature of the attack means that exploitation can occur from anywhere on the internet without requiring physical access to the target network. This vulnerability directly maps to several ATT&CK techniques including T1566 for social engineering and T1059 for command and scripting interpreter usage, as attackers can leverage this flaw to execute malicious code remotely.
Organizations should immediately implement input validation and output encoding mechanisms throughout their web applications to prevent similar vulnerabilities from occurring. The recommended mitigations include implementing proper parameter validation, using secure coding practices such as context-aware output encoding, and deploying web application firewalls to detect and block malicious payloads. Regular security testing including automated scanning and manual penetration testing should be conducted to identify and remediate similar vulnerabilities before they can be exploited by threat actors. Additionally, maintaining up-to-date software versions and implementing defense-in-depth strategies including network segmentation and access controls will significantly reduce the overall risk exposure associated with this type of vulnerability.