CVE-2025-30667 is a vulnerability identified in Zoom Communications, Inc's Zoom Workplace Apps for Windows. The issue is classified as a NULL pointer dereference (CWE-476), which occurs when the application attempts to access or dereference a pointer that has not been initialized or has been set to NULL. This flaw can be triggered by an authenticated user through network access, leading to a denial of service (DoS) condition. Specifically, the vulnerability allows an attacker with valid credentials to cause the Zoom Workplace App to crash or become unresponsive by exploiting the NULL pointer dereference. The vulnerability does not impact confidentiality or integrity but affects availability, as the app may stop functioning correctly, disrupting communication and collaboration workflows. The CVSS v3.1 base score is 6.5, indicating a medium severity level. The attack vector is network-based (AV:N), requiring low attack complexity (AC:L) and privileges (PR:L), but no user interaction (UI:N). The scope remains unchanged (S:U), and the impact is limited to availability (A:H) without affecting confidentiality or integrity. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was reserved in March 2025 and published in May 2025, indicating it is a recent discovery. Given the widespread use of Zoom Workplace Apps in enterprise environments, this vulnerability could disrupt business operations if exploited.

For European organizations, this vulnerability poses a risk primarily to the availability of Zoom Workplace Apps, which are commonly used for internal communication, meetings, and collaboration. A successful denial of service attack could interrupt critical business communications, delay decision-making processes, and reduce productivity. Sectors heavily reliant on real-time collaboration, such as finance, healthcare, and government agencies, may experience operational disruptions. Although the vulnerability requires authenticated access, insider threats or compromised credentials could be leveraged to exploit this flaw. The medium severity rating suggests that while the impact is not catastrophic, it can still cause significant inconvenience and potential financial losses due to downtime. Additionally, organizations with strict service level agreements (SLAs) or regulatory requirements for uptime may face compliance challenges. The absence of known exploits provides a window for mitigation before active exploitation occurs.

European organizations should implement the following specific mitigation measures: 1) Monitor and restrict access to Zoom Workplace Apps by enforcing strong authentication mechanisms and limiting user privileges to the minimum necessary. 2) Implement network segmentation and access controls to reduce the attack surface and prevent unauthorized lateral movement within the network. 3) Maintain up-to-date inventories of Zoom Workplace App versions in use and subscribe to vendor advisories to promptly apply patches once available. 4) Employ application whitelisting and endpoint protection solutions to detect and prevent abnormal application behavior indicative of exploitation attempts. 5) Conduct regular security awareness training to reduce the risk of credential compromise. 6) Establish incident response procedures to quickly identify and mitigate denial of service incidents affecting collaboration tools. 7) Consider deploying redundancy or alternative communication platforms to maintain business continuity during potential service disruptions.