CVE-2022-41741 is a high-severity vulnerability classified as CWE-787 (Out-of-bounds Write) affecting multiple versions of NGINX products developed by F5, including NGINX Open Source (before versions 1.23.2 and 1.22.1), NGINX Open Source Subscription (before R2 P1 and R1 P1), and NGINX Plus (before R27 P1 and R26 P1). The vulnerability resides in the ngx_http_mp4_module, which is responsible for handling MP4 streaming and processing of audio/video files. Specifically, when the mp4 directive is enabled in the NGINX configuration, a local attacker with limited privileges can exploit this vulnerability by supplying a specially crafted audio or video file. This crafted file triggers an out-of-bounds write in the worker process memory, potentially leading to memory corruption. The immediate consequence is the termination of the affected NGINX worker process, which impacts availability. However, due to the nature of memory corruption, other impacts such as arbitrary code execution or further compromise cannot be ruled out, although no known exploits are reported in the wild to date. Exploitation requires local access with low privileges, no user interaction is needed, and the attack complexity is high due to the need for crafting a malicious media file and triggering its processing. The vulnerability affects only NGINX instances built with the ngx_http_mp4_module and configured to use the mp4 directive, limiting the attack surface to deployments that serve MP4 content via this module. The CVSS v3.1 base score is 7.0, reflecting high impact on confidentiality, integrity, and availability, but with attack vector limited to local access and high attack complexity.

For European organizations, this vulnerability poses a significant risk primarily to web servers and streaming platforms that utilize NGINX with the ngx_http_mp4_module enabled. Organizations in media, entertainment, education, and any sector delivering video content via NGINX could face service disruptions due to worker process crashes, resulting in denial of service conditions. The potential for memory corruption raises concerns about possible privilege escalation or unauthorized code execution, which could lead to broader network compromise if exploited in chained attacks. Given the local access requirement, the threat is more pronounced in environments where untrusted users have some level of access to upload or trigger processing of media files, such as multi-tenant hosting providers, cloud services, or internal networks with less stringent access controls. The impact on confidentiality and integrity is high if an attacker leverages this vulnerability to execute arbitrary code or escalate privileges. Availability is also at risk due to worker process termination. European organizations with strict data protection regulations (e.g., GDPR) must consider the implications of potential data breaches stemming from exploitation. Additionally, disruption of critical services or customer-facing platforms could lead to reputational damage and financial loss.

To mitigate CVE-2022-41741, European organizations should: 1) Immediately upgrade affected NGINX products to the fixed versions (1.23.2, 1.22.1 for Open Source; R2 P1, R1 P1 for Open Source Subscription; R27 P1, R26 P1 for NGINX Plus) as provided by F5. 2) If immediate patching is not feasible, disable the ngx_http_mp4_module or avoid using the mp4 directive in the NGINX configuration to eliminate the attack surface. 3) Restrict local access to systems running vulnerable NGINX instances, ensuring that only trusted users can upload or trigger processing of media files. 4) Implement strict input validation and file integrity checks on uploaded media content to detect and block malformed or suspicious files. 5) Monitor NGINX worker processes for unexpected crashes or abnormal behavior indicative of exploitation attempts. 6) Employ application-layer firewalls or intrusion detection systems tuned to detect anomalous MP4 file processing. 7) Conduct regular security audits and vulnerability scans focusing on media processing modules. 8) Educate system administrators and developers about the risks associated with enabling optional modules and the importance of timely patching.