CVE-2025-46788 is a high-severity vulnerability identified in Zoom Communications Inc.'s Zoom Workplace client for Linux, specifically in versions prior to 6.4.13. The vulnerability stems from improper certificate validation (classified under CWE-295), which means the application fails to correctly verify the authenticity of TLS/SSL certificates during network communications. This flaw can be exploited by an unauthorized attacker with network access to intercept or manipulate communications, potentially leading to information disclosure. Since the vulnerability does not require any privileges or user interaction (AV:N/PR:N/UI:N), it can be exploited remotely over the network, although the attack complexity is rated high (AC:H), indicating some non-trivial conditions or skills are necessary to successfully exploit it. The impact primarily affects confidentiality and integrity, allowing attackers to potentially eavesdrop on or alter sensitive data transmitted by the Zoom Workplace client on Linux systems. The vulnerability does not affect availability. No known exploits are currently reported in the wild, but the presence of this flaw in a widely used communication tool poses a significant risk if left unpatched. The lack of a patch link suggests that users should monitor Zoom's official channels for updates and apply the fixed version 6.4.13 or later once available.

For European organizations, this vulnerability presents a considerable risk, especially for entities relying on Zoom Workplace for Linux for internal and external communications. The improper certificate validation could allow attackers, including state-sponsored actors or cybercriminals, to conduct man-in-the-middle (MitM) attacks, leading to unauthorized disclosure of sensitive corporate information, intellectual property, or personal data protected under GDPR. This could result in regulatory penalties, reputational damage, and operational disruptions. Organizations in sectors such as finance, healthcare, government, and critical infrastructure, which often use Linux-based systems and require secure communications, are particularly vulnerable. The remote exploitation capability without user interaction increases the threat surface, especially in environments with less stringent network segmentation or monitoring. Additionally, the high attack complexity may limit widespread exploitation but does not eliminate targeted attacks against high-value European targets.

European organizations should prioritize upgrading Zoom Workplace for Linux to version 6.4.13 or later as soon as it becomes available. Until then, they should implement network-level mitigations such as enforcing strict TLS inspection policies, using network segmentation to isolate Linux clients running Zoom Workplace, and deploying intrusion detection/prevention systems tuned to detect anomalous TLS certificate behaviors. Organizations should also enforce the use of VPNs or secure tunnels that provide additional encryption layers beyond Zoom's own mechanisms. Regularly auditing and monitoring network traffic for signs of MitM attacks or certificate anomalies is critical. Security teams should educate users about the risks of connecting to untrusted networks and consider temporarily restricting Zoom Workplace usage on Linux systems in high-risk environments. Finally, organizations should maintain up-to-date asset inventories to identify affected Linux clients and ensure timely patch management.