CVE-2023-41707 is a vulnerability identified in the Open-Xchange GmbH OX App Suite, a widely used collaborative mail and productivity platform. The issue arises from the lack of limits on processing user-defined mail search expressions, which can be crafted to consume excessive server resources. This uncontrolled resource consumption can lead to degraded performance or denial of service (DoS) conditions, impacting the availability of the OX App Suite. The vulnerability requires an attacker to have low-level privileges (PR:L) but does not require user interaction (UI:N) and can be exploited remotely (AV:N). The CVSS v3.1 base score is 6.5, reflecting a medium severity primarily due to its impact on availability (A:H), with no impact on confidentiality or integrity. The vendor has addressed the issue by introducing monitoring of mail search processing times and terminating requests that exceed predefined resource thresholds, thereby preventing excessive load. No public exploits have been reported, but the vulnerability remains a concern for organizations relying on OX App Suite for email and collaboration services. The affected versions are not explicitly detailed but are implied to be all prior to the patch. This vulnerability highlights the risks of insufficient input validation and resource management in complex search functionalities within enterprise software.

For European organizations, the primary impact of CVE-2023-41707 is the potential disruption of email and collaboration services provided by OX App Suite. This can lead to reduced productivity, communication delays, and operational downtime, especially in organizations heavily dependent on this platform for daily business activities. Since the vulnerability affects availability without compromising confidentiality or integrity, the risk is mainly service interruption rather than data breach. However, denial of service in critical communication systems can have cascading effects on business operations, customer service, and regulatory compliance, particularly in sectors like finance, healthcare, and government. The ease of exploitation by low-privilege users increases the risk from insider threats or compromised accounts. European organizations with large user bases or high mail traffic volumes may experience amplified effects due to resource exhaustion. The absence of public exploits currently reduces immediate risk but does not eliminate the threat, making timely patching essential to maintain service continuity.

Organizations should promptly apply the vendor-provided patches and updates that implement processing time monitoring and request termination for excessive resource consumption. Beyond patching, administrators should audit and restrict permissions to limit who can perform complex mail searches, reducing the attack surface. Implementing rate limiting on mail search requests can help prevent abuse. Monitoring server performance metrics and mail search request logs will aid in early detection of abnormal resource usage patterns. Network-level protections such as web application firewalls (WAFs) can be configured to detect and block suspicious search queries. Regularly reviewing and updating access controls and user privileges will minimize the risk of exploitation by unauthorized or compromised accounts. Additionally, organizations should maintain incident response plans that include scenarios for denial-of-service events affecting mail services. Coordination with the vendor for ongoing updates and security advisories is recommended to stay ahead of emerging threats related to this vulnerability.