CVE-2025-49458 is a medium severity buffer overflow vulnerability identified in Zoom Communications, Inc's Zoom Workplace Clients. The underlying issue is classified as CWE-120, which involves a classic buffer copy operation without proper validation of the input size. This vulnerability allows an authenticated user to trigger a denial of service (DoS) condition via network access. Specifically, the flaw arises when the application copies data into a buffer without checking if the input size exceeds the buffer's capacity, leading to memory corruption. While the vulnerability does not impact confidentiality or integrity directly, it affects availability by potentially crashing the Zoom Workplace Client or causing it to become unresponsive. The CVSS 3.1 base score of 6.5 reflects a medium severity level, with the vector indicating that the attack can be performed remotely over the network (AV:N), requires low attack complexity (AC:L), but requires privileges (PR:L) meaning the attacker must be an authenticated user. No user interaction is needed (UI:N), and the scope remains unchanged (S:U). There are no known exploits in the wild at the time of publication, and no patches or mitigations have been linked yet. The affected versions are unspecified but presumably include certain versions of Zoom Workplace Clients released prior to the patch. This vulnerability is significant because Zoom Workplace Clients are widely used for enterprise collaboration, and a DoS attack could disrupt business communications and workflows.

For European organizations, the impact of this vulnerability could be considerable, especially for those relying heavily on Zoom Workplace Clients for internal and external communications. A successful exploitation would result in denial of service, causing interruptions in meetings, collaboration sessions, and potentially delaying critical business operations. This could be particularly damaging in sectors where continuous communication is essential, such as finance, healthcare, government, and critical infrastructure. Although the vulnerability does not allow data theft or code execution, the availability impact could lead to operational downtime, loss of productivity, and reputational damage. Additionally, since the attack requires authentication, insider threats or compromised user credentials could be leveraged to exploit this vulnerability. The lack of known exploits currently reduces immediate risk, but the presence of a buffer overflow vulnerability is concerning due to the potential for future escalation or exploitation variants.

European organizations should prioritize the following mitigation steps: 1) Monitor official Zoom communications for patches addressing CVE-2025-49458 and apply updates promptly once available. 2) Enforce strict access controls and multi-factor authentication (MFA) to reduce the risk of unauthorized or malicious authenticated users exploiting this vulnerability. 3) Implement network segmentation and limit access to Zoom Workplace Clients to trusted networks and users to minimize exposure. 4) Employ endpoint protection solutions capable of detecting anomalous application crashes or behavior indicative of exploitation attempts. 5) Conduct regular user training to recognize phishing or credential compromise attempts that could lead to unauthorized authenticated access. 6) Consider temporary workarounds such as disabling or restricting certain Zoom Workplace Client features if recommended by Zoom until patches are released. 7) Maintain robust incident response plans to quickly address any DoS incidents affecting communication platforms.