CVE-2025-7799 is a reflected Cross-site Scripting (XSS) vulnerability classified under CWE-79, affecting the e-Taxpayer Accounting Website developed by Zirve Information Technologies Inc. The vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, allowing attackers to inject malicious scripts that are reflected back to the victim's browser. This flaw can be exploited remotely without requiring any authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The impact on confidentiality is limited because the attacker can only access data accessible to the victim's browser session, but the integrity impact is high since attackers can execute arbitrary scripts, potentially manipulating data or performing unauthorized actions on behalf of the user. Availability impact is low, as the vulnerability does not directly disrupt service. The vulnerability affects all versions up to 07/08/2025 of the e-Taxpayer Accounting Website. Although no known exploits are currently reported in the wild, the high CVSS score (8.6) underscores the criticality of this issue. The vulnerability was reserved on 2025-07-18 and published on 2026-02-09 by TR-CERT. The absence of patches at this time highlights the urgency for organizations to implement interim mitigations. Given the nature of tax accounting platforms, exploitation could lead to significant financial and reputational damage. The reflected XSS could be used to steal session cookies, redirect users to malicious sites, or perform actions with the victim’s privileges within the application. The vulnerability is particularly concerning for European organizations that rely on this platform for tax reporting and compliance, as attackers could leverage it to disrupt tax processes or exfiltrate sensitive financial data.

For European organizations, the impact of CVE-2025-7799 is significant due to the critical role of tax accounting systems in regulatory compliance and financial operations. Exploitation could allow attackers to execute arbitrary scripts in the context of authenticated users, potentially leading to session hijacking, unauthorized data manipulation, or phishing attacks targeting tax officials and accountants. This could result in data integrity breaches, financial fraud, and loss of trust in tax systems. Confidentiality impact is moderate since attackers gain access only to data visible to the victim's session, but the high integrity impact can cause severe operational disruptions. Availability impact is low but cannot be entirely dismissed if attackers use the vulnerability to inject disruptive scripts. European tax authorities and organizations using the Zirve e-Taxpayer platform may face regulatory penalties and reputational damage if exploited. The lack of known exploits currently provides a window for proactive mitigation, but the ease of exploitation (no authentication or user interaction needed) increases the urgency. Attackers could target this vulnerability to gain footholds in critical financial infrastructure, especially in countries with high adoption of this software.

1. Implement strict input validation and output encoding on all user-supplied data to prevent script injection. 2. Apply context-aware escaping for HTML, JavaScript, and URL contexts within the web application. 3. Deploy a robust Content Security Policy (CSP) to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. 4. Conduct thorough code reviews focusing on input handling and sanitization in the e-Taxpayer Accounting Website. 5. Monitor web server and application logs for unusual request patterns indicative of XSS exploitation attempts. 6. Educate users and administrators about the risks of XSS and encourage cautious behavior regarding suspicious links or inputs. 7. Engage with Zirve Information Technologies Inc. to obtain patches or updates as soon as they become available. 8. Consider implementing Web Application Firewalls (WAF) with rules tailored to detect and block reflected XSS payloads targeting this application. 9. Isolate the e-Taxpayer platform within network segments with strict access controls to limit lateral movement if exploited. 10. Regularly update and patch all related infrastructure components to reduce the attack surface.