CVE-2025-67823 is a security vulnerability identified in the Multimedia Email component of Mitel MiContact Center Business (versions through 10.2.0.10) and Mitel CX (through 1.1.0.1). The flaw arises from insufficient input validation in the email processing functionality, which enables an unauthenticated attacker to perform a Cross-Site Scripting (XSS) attack. Specifically, when the email channel is enabled, an attacker can craft malicious email content that, upon user interaction, executes arbitrary scripts within the context of the victim’s browser or the Mitel desktop client application. This execution context allows the attacker to potentially steal session cookies, perform actions on behalf of the user, or deliver further malware payloads. The vulnerability requires user interaction, such as clicking or opening a malicious email, which limits automated exploitation but still poses a significant risk in social engineering scenarios. No public exploits have been reported, and no official patches or CVSS scores are currently available, though the vulnerability has been published and reserved in the CVE database. The affected products are widely used in enterprise contact center environments, which handle sensitive customer communications and data. The lack of input sanitization in the multimedia email component is a critical oversight, as it directly impacts the confidentiality and integrity of user sessions and data. The vulnerability’s exploitation could disrupt business operations and lead to data breaches or reputational damage. Given the nature of the vulnerability, it primarily affects the confidentiality and integrity of affected systems, with availability impact being minimal unless combined with other attack vectors. The attack vector is remote and unauthenticated but requires user interaction, which somewhat reduces the risk of widespread automated exploitation. Organizations relying on Mitel’s contact center solutions should prioritize identifying affected versions and preparing for patch deployment once available. In the interim, disabling the email channel or restricting email content types may reduce exposure. Additionally, implementing Content Security Policies (CSP) and educating users about phishing risks can mitigate exploitation likelihood.

For European organizations, the impact of CVE-2025-67823 can be significant, especially for those heavily dependent on Mitel MiContact Center Business and Mitel CX solutions for customer engagement and communication. Successful exploitation could lead to unauthorized script execution, enabling attackers to hijack user sessions, steal sensitive customer data, or manipulate communications, potentially resulting in data breaches and compliance violations under GDPR. The contact center environment often processes personal and financial information, increasing the risk of privacy infringements and financial fraud. Operational disruption may occur if attackers leverage the vulnerability to spread malware or conduct phishing campaigns internally. The requirement for user interaction limits automated mass exploitation but does not eliminate targeted spear-phishing risks. European organizations with large customer service operations, particularly in finance, telecommunications, and public sectors, may face reputational damage and regulatory scrutiny if exploited. The absence of a patch at the time of disclosure necessitates immediate risk management and mitigation efforts to prevent exploitation. Additionally, attackers could use this vulnerability as a foothold for further lateral movement within networks, increasing overall organizational risk.

1. Monitor Mitel’s official channels for patches addressing CVE-2025-67823 and apply them promptly upon release. 2. Temporarily disable or restrict the Multimedia Email channel in Mitel MiContact Center Business and Mitel CX if feasible, to reduce attack surface. 3. Implement strict input validation and sanitization on all email content processed by the contact center systems, if customization is possible. 4. Deploy Content Security Policies (CSP) in browsers and desktop clients to limit script execution from untrusted sources. 5. Educate users and contact center staff about phishing and social engineering risks, emphasizing caution when interacting with unexpected or suspicious emails. 6. Employ email filtering solutions to detect and block malicious payloads before reaching end users. 7. Conduct regular security assessments and penetration testing focused on contact center infrastructure. 8. Monitor logs and network traffic for unusual activity indicative of exploitation attempts. 9. Segment contact center networks to limit lateral movement in case of compromise. 10. Coordinate with Mitel support and cybersecurity teams to stay informed on vulnerability developments and remediation strategies.