CVE-2025-30669 is a vulnerability identified in Zoom Communications Inc.'s Zoom Workplace Clients, characterized by improper certificate validation (CWE-295). This weakness occurs when the client software fails to correctly validate SSL/TLS certificates, potentially allowing an unauthenticated attacker with adjacent network access to intercept or disclose sensitive information. The attack vector is adjacent network (AV:A), meaning the attacker must be on the same local network segment or have similar proximity, such as a shared Wi-Fi network. The attack complexity is high (AC:H), indicating that exploitation requires specific conditions or expertise. No privileges are required (PR:N), but user interaction is necessary (UI:R), which may involve the victim performing certain actions like connecting to a malicious server or clicking a link. The vulnerability impacts confidentiality (C:H) but does not affect integrity or availability. The scope is unchanged (S:U), meaning the vulnerability affects only the vulnerable component without impacting other system components. The CVSS score of 4.8 reflects a medium severity level. No known exploits have been reported in the wild, and no patches have been published at the time of analysis. This vulnerability could lead to information disclosure, such as leaking sensitive communication metadata or session information, which could be leveraged for further attacks or espionage. The root cause lies in inadequate certificate validation logic within the Zoom Workplace Clients, which may accept invalid or malicious certificates, undermining the trust model of secure communications.

For European organizations, this vulnerability poses a risk of sensitive information disclosure, particularly in environments where employees use Zoom Workplace Clients over shared or unsecured local networks, such as public Wi-Fi or corporate guest networks. Confidential data, including meeting metadata or session details, could be exposed to nearby attackers, potentially facilitating espionage or targeted attacks. While the vulnerability does not allow direct code execution or system compromise, the leakage of information could undermine privacy and compliance with data protection regulations like GDPR. Organizations with extensive remote workforces or those relying heavily on Zoom for internal communications are at greater risk. The medium severity and high attack complexity reduce the likelihood of widespread exploitation but do not eliminate the threat, especially in high-value targets or sectors handling sensitive data such as finance, healthcare, or government. The absence of known exploits suggests a window for proactive mitigation before active attacks emerge.

European organizations should implement network segmentation and restrict access to trusted networks to minimize adjacent network exposure. Use VPNs or secure tunnels to protect Zoom traffic when operating over untrusted networks. Educate users to avoid connecting to unknown or unsecured Wi-Fi networks and to be cautious of unexpected prompts or links within Zoom clients. Monitor network traffic for anomalies indicative of man-in-the-middle attempts or certificate spoofing. Deploy endpoint security solutions capable of detecting unusual certificate validation behavior. Stay informed on Zoom's security advisories and apply patches promptly once available. Consider temporary use of alternative secure communication platforms if patching is delayed. Additionally, enforce strict certificate pinning policies where feasible and audit client configurations to ensure proper certificate validation settings are enabled. Collaborate with IT and security teams to conduct penetration testing simulating adjacent network attacks to assess exposure.