CVE-2025-53783 is a high-severity heap-based buffer overflow vulnerability identified in Microsoft Teams specifically for the Dynamics 365 Remote Assist application running on Microsoft HoloLens devices. The vulnerability arises from improper handling of memory buffers within the Teams client, allowing an attacker to overflow a heap buffer. This type of vulnerability can lead to arbitrary code execution, enabling an attacker to run malicious code remotely without requiring prior authentication. The CVSS v3.1 score of 7.5 reflects the significant impact on confidentiality, integrity, and availability, with the attack vector being network-based but requiring high attack complexity and user interaction. The vulnerability affects version 316.0000 of the product. Although no public exploits are currently known, the potential for remote code execution makes this a critical concern for organizations utilizing this technology. The lack of available patches at the time of publication increases the urgency for mitigation and monitoring. The vulnerability is classified under CWE-122, which is a common and dangerous class of memory corruption bugs that often lead to severe security breaches.

For European organizations, the impact of this vulnerability could be substantial, especially for those leveraging Microsoft Teams for D365 Remote Assist on HoloLens devices in industrial, manufacturing, or remote collaboration scenarios. Exploitation could lead to unauthorized access to sensitive corporate data, disruption of remote assistance workflows, and potential lateral movement within networks. Given the integration of Teams in enterprise communication and collaboration, a successful exploit could compromise confidentiality and integrity of communications and data. Additionally, availability could be affected if the exploit leads to application crashes or system instability. The remote and unauthenticated nature of the attack vector increases the risk profile, particularly for organizations with remote or hybrid workforces using augmented reality tools. The absence of known exploits currently provides a window for proactive defense, but the high severity score indicates that exploitation could have serious operational and reputational consequences.

Organizations should immediately inventory their use of Microsoft Teams for D365 Remote Assist on HoloLens devices and verify the version in use. Until a patch is released, applying strict network segmentation and firewall rules to limit exposure of HoloLens devices to untrusted networks is critical. Employing application whitelisting and endpoint detection and response (EDR) solutions can help detect anomalous behavior indicative of exploitation attempts. User education to avoid interacting with suspicious links or content within Teams is important given the requirement for user interaction. Monitoring network traffic for unusual patterns related to Teams communications may provide early warning signs. Once Microsoft releases a patch, organizations must prioritize rapid deployment. Additionally, disabling or restricting the use of the affected Teams client on HoloLens devices where feasible until patched can reduce risk. Regularly reviewing and updating security policies around augmented reality and remote assist technologies will further strengthen defenses.