CVE-2022-41676 is a reflected Cross-Site Scripting (XSS) vulnerability identified in version 4.7 of the MAILD Mail Server developed by TEAM JOHNLONG SOFTWARE CO., LTD. The vulnerability arises due to insufficient input filtering on the website's mail field, which allows a remote attacker with general user privileges to inject malicious JavaScript code into the input. When the crafted email is sent through the web interface, the malicious script is reflected and executed in the context of the mail recipient's browser. This type of XSS attack exploits the CWE-85 doubled character manipulation technique, which involves bypassing input validation by using doubled characters to evade detection and filtering mechanisms. The vulnerability does not require elevated privileges beyond general user access, nor does it require prior authentication beyond the ability to send emails via the web interface. No known exploits have been reported in the wild as of the published date, and no official patches or mitigation links have been provided by the vendor. The vulnerability primarily threatens the confidentiality and integrity of the recipient's browsing session by potentially allowing session hijacking, credential theft, or execution of arbitrary scripts within the victim's browser environment. The attack vector is remote and requires user interaction only in the form of the recipient opening or interacting with the malicious email content. Given the nature of reflected XSS, the scope of affected systems includes any user accessing the vulnerable mail server's web interface and receiving emails processed through it.

For European organizations using MAILD Mail Server version 4.7, this vulnerability poses a risk of client-side attacks that can lead to credential compromise, session hijacking, or further malware delivery through the execution of malicious scripts in recipients' browsers. This can undermine trust in corporate email communications, potentially leading to data breaches or unauthorized access to internal systems if attackers leverage stolen credentials or session tokens. Organizations in sectors with high reliance on secure email communications—such as finance, healthcare, and government—may face increased risks of targeted phishing campaigns exploiting this vulnerability. Additionally, the reflected XSS can be used to bypass security controls and deliver secondary payloads, amplifying the impact. Although the vulnerability does not directly compromise the mail server's backend systems, the exploitation can facilitate lateral movement or social engineering attacks within the organization. The absence of known exploits in the wild suggests limited current threat activity, but the medium severity rating and ease of exploitation warrant proactive mitigation to prevent future attacks.

1. Immediate mitigation should include implementing strict input validation and output encoding on the mail field to neutralize malicious scripts, specifically addressing doubled character manipulations as per CWE-85 guidelines. 2. Organizations should monitor and restrict the use of MAILD Mail Server version 4.7 and consider upgrading to a patched or newer version once available. 3. Deploy Web Application Firewalls (WAFs) with custom rules to detect and block reflected XSS payloads targeting the mail field, including patterns involving doubled characters. 4. Educate end-users on recognizing suspicious email content and encourage cautious interaction with emails received via the vulnerable server. 5. Implement Content Security Policy (CSP) headers on the mail server's web interface to restrict the execution of unauthorized scripts. 6. Conduct regular security assessments and penetration testing focusing on input validation weaknesses in webmail interfaces. 7. If patching is not immediately possible, consider isolating or restricting access to the vulnerable webmail interface to trusted networks or VPN users only. 8. Log and monitor email sending activities for anomalies that may indicate exploitation attempts.