CVE-2025-49028 identifies a Cross-Site Request Forgery (CSRF) vulnerability in Zoho ZeptoMail, a cloud-based email service product from Zoho Mail, affecting versions up to 3.3.1. CSRF vulnerabilities allow attackers to trick authenticated users into submitting unwanted requests to a web application, exploiting the user's active session without their consent. In this case, the CSRF flaw enables stored Cross-Site Scripting (XSS), where malicious scripts injected by the attacker persist on the server and execute in the context of other users' browsers. The vulnerability does not require prior authentication (PR:N) but does require user interaction (UI:R), such as clicking a malicious link or visiting a crafted webpage. The CVSS 3.1 score of 7.1 reflects a high severity, with network attack vector (AV:N), low attack complexity (AC:L), and impacts on confidentiality, integrity, and availability (C:L/I:L/A:L). The scope is changed (S:C), indicating that exploitation affects resources beyond the vulnerable component. Although no public exploits are currently known, the combination of CSRF and stored XSS can lead to session hijacking, data theft, or unauthorized actions within the affected Zoho ZeptoMail environment. The vulnerability was reserved in May 2025 and published at the end of 2025, with no patches currently linked, suggesting that remediation is pending or in progress.

For European organizations, the impact of CVE-2025-49028 can be significant, especially for those relying on Zoho ZeptoMail for critical email communications. Successful exploitation could lead to unauthorized actions performed under the guise of legitimate users, including sending emails, modifying account settings, or injecting malicious scripts that compromise user data and privacy. This can result in data breaches, loss of sensitive information, reputational damage, and potential regulatory penalties under GDPR. The stored XSS component increases the risk by enabling persistent attacks that can affect multiple users and systems. Given the interconnected nature of email services, attackers could leverage this vulnerability to pivot to other internal systems or launch phishing campaigns. The requirement for user interaction means social engineering could be a key vector, increasing the risk in environments with less security awareness. The high severity and scope change indicate that the vulnerability could impact multiple tenants or services within Zoho's infrastructure, amplifying the potential damage.

Organizations should prioritize monitoring Zoho's official security advisories for patches addressing CVE-2025-49028 and apply them immediately upon release. In the interim, implement strict Content Security Policies (CSP) to mitigate the impact of stored XSS attacks. Employ anti-CSRF tokens and verify the origin and referer headers on all state-changing requests within Zoho ZeptoMail interfaces if customization or API access is available. Enhance user training to recognize phishing attempts and suspicious links that could trigger CSRF attacks. Network-level protections such as web application firewalls (WAFs) can be configured to detect and block CSRF attack patterns and malicious payloads. Additionally, organizations should review and limit permissions for Zoho ZeptoMail users to the minimum necessary, reducing the potential impact of compromised accounts. Regular security audits and penetration testing focused on email platforms can help identify residual risks. Finally, consider multi-factor authentication (MFA) enforcement to add an additional layer of defense against unauthorized actions.