CVE-2026-79419 in Gestao X Business Suite
Summary
by MITRE • 09/04/2026
A reflected cross-site scripting (XSS) vulnerability exists in EMX Tecnologia Gestao X Business Suite 8.4 and earlier. The vulnerability is caused by insufficient validation and sanitization of the mensagem parameter in the /Configuracao/Imagens.aspx endpoint, allowing an authenticated attacker to inject arbitrary JavaScript code that is reflected and executed in the context of a victim's browser.
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Analysis
by VulDB Data Team • 09/06/2026
The identified security flaw represents a classic instance of Reflected Cross-Site Scripting within the EMX Tecnologia Gestao X Business Suite version 8.4 and earlier iterations. This vulnerability specifically targets the /Configuracao/Imagens.aspx endpoint, where the application fails to adequately validate or sanitize user-supplied input passed via the mensagem parameter. In a typical web application architecture, parameters transmitted through URLs are often processed directly by server-side scripts without sufficient scrutiny for malicious content. When an attacker crafts a specially constructed URL containing embedded JavaScript code within this specific parameter and tricks a victim into visiting it, the vulnerable server reflects the untrusted data back in the HTTP response. The browser then interprets this injected script as part of the legitimate page content, leading to its execution within the security context of the application domain.
From a technical perspective, the root cause lies in insufficient input validation and output encoding mechanisms at the /Configuracao/Imagens.aspx endpoint. The server-side logic accepts the mensagem parameter and incorporates it into the HTML response without stripping out script tags or escaping special characters that could trigger code execution. This lack of sanitization allows an unauthenticated attacker to bypass any existing access controls, as no prior authentication is required to exploit this flaw. The attack vector relies on social engineering tactics where a victim must be induced to click a malicious link, which serves as the delivery mechanism for the payload. Once executed, the injected JavaScript runs with the same privileges and permissions as legitimate scripts loaded by the browser, granting the attacker significant control over the client-side environment.
The operational impact of this vulnerability is severe due to its potential for session hijacking and data theft. An attacker can exploit the reflected XSS to steal sensitive information such as session cookies, which are often used to maintain user authentication states. By capturing these tokens, an adversary can impersonate legitimate users, gaining unauthorized access to their accounts and potentially escalating privileges within the business suite. Furthermore, the vulnerability enables phishing attacks where malicious content is injected directly into trusted pages, increasing the likelihood of success since victims perceive the source as trustworthy. In more complex scenarios, attackers could use this vector to deface web pages or redirect users to malicious sites designed to distribute malware or harvest credentials through fake login forms that mimic legitimate interfaces.
This vulnerability aligns with Common Weakness Enumeration identifier CWE-79, which classifies improper neutralization of input during web page generation as a Cross-site Scripting weakness. The exploitation technique corresponds to the ATT&CK framework tactic T1059, specifically sub-technique 007 for Command and Scripting Interpretation via JavaScript in browser-based contexts. To mitigate this risk, developers must implement strict input validation on all user-supplied parameters, ensuring that only expected data types and formats are accepted. Additionally, output encoding should be applied consistently to special characters before they are rendered in HTML responses, preventing the browser from interpreting them as executable code. Implementing a Content Security Policy header can also provide an additional layer of defense by restricting the sources from which scripts can be loaded or executed. Regular security testing and code reviews focusing on input handling practices are essential to prevent similar vulnerabilities in future releases of the software.