CVE-2025-59902 is an HTML injection vulnerability classified under CWE-79 (Improper Neutralization of Input During Web Page Generation) found in NICE Chat, a widely used customer interaction platform. The vulnerability arises because the application fails to properly sanitize the 'firstName' and 'lastName' input parameters during chat sessions. An attacker can exploit this by injecting malicious HTML code into these parameters, which is then embedded into the body of email transcripts generated and sent by the system. This flaw enables attackers to craft emails that appear legitimate but contain malicious content, facilitating phishing attacks, impersonation of users or support agents, and potential credential theft. The vulnerability is remotely exploitable without authentication (AV:N/AC:L/PR:N), but requires user interaction (UI:P) to trigger the malicious email. The impact on confidentiality is limited but significant due to the potential for credential theft, while integrity and availability impacts are low. The vulnerability affects all versions of NICE Chat, and as of the publication date, no patches or known exploits have been reported. The CVSS 4.0 vector indicates a high severity score of 7.1, emphasizing the need for prompt remediation. The vulnerability's exploitation vector through email transcripts makes it a potent vector for social engineering attacks, especially in environments where NICE Chat is integrated into customer service workflows.

For European organizations, this vulnerability poses a substantial risk primarily through social engineering and phishing attacks. Since NICE Chat is often used in customer support and communication, attackers can exploit this flaw to send malicious emails that appear to originate from trusted sources, increasing the likelihood of successful phishing campaigns. This can lead to credential theft, unauthorized access to sensitive systems, and potential data breaches. The reputational damage and regulatory consequences under GDPR for failing to protect customer data could be significant. Additionally, organizations relying heavily on NICE Chat for customer interactions may experience operational disruptions if phishing attacks lead to compromised accounts or internal security incidents. The risk is amplified in sectors such as finance, telecommunications, and public services, where customer trust and data protection are paramount. The lack of available patches means organizations must rely on mitigations and monitoring until an official fix is released.

1. Implement strict input validation and sanitization on all user-supplied data, especially the 'firstName' and 'lastName' fields, to prevent injection of HTML or script content. 2. Sanitize and encode email transcript content before sending to ensure that any injected HTML is rendered harmless or displayed as plain text. 3. Employ Content Security Policy (CSP) headers where applicable to limit the execution of injected scripts in email clients that support CSP. 4. Monitor outgoing emails for suspicious or malformed content that could indicate exploitation attempts. 5. Educate employees and customers about phishing risks, emphasizing caution with unexpected emails even if they appear to come from trusted sources. 6. Restrict or log changes to user profile fields that can influence email content to detect anomalous input patterns. 7. Engage with NICE to obtain patches or updates as soon as they become available and apply them promptly. 8. Consider deploying email security gateways with advanced phishing detection capabilities to filter malicious emails before reaching end users. 9. Review and harden email client configurations to disable automatic execution of scripts or HTML content where possible.