CVE-2025-46391 is a medium-severity vulnerability identified in Emby MediaBrowser version 4.9.0.35. The vulnerability is classified under CWE-284, which refers to improper access control. Specifically, this flaw allows an attacker with some level of privileges (PR:L - privileges required: low) to perform unauthorized actions that impact the integrity of the system without requiring user interaction (UI:N). The vulnerability is remotely exploitable (AV:N) over the network without physical access. The CVSS v3.1 base score is 6.5, indicating a moderate risk. The attack does not affect confidentiality or availability but can compromise the integrity of the MediaBrowser application or its data. Improper access control means that certain functions or resources within Emby MediaBrowser are not adequately protected, allowing an attacker with limited privileges to escalate their capabilities or modify data in ways they should not be able to. Since no known exploits are currently in the wild and no patches have been linked yet, the risk is present but not actively exploited. Emby MediaBrowser is a media server software used to organize, stream, and share media content across devices, often deployed in home and small business environments. The vulnerability could allow an attacker to manipulate media content or settings, potentially disrupting service or corrupting data integrity.

For European organizations using Emby MediaBrowser, particularly those relying on it for media streaming and content management, this vulnerability could lead to unauthorized modification of media libraries or configurations. While it does not directly compromise confidentiality or availability, the integrity impact could disrupt business operations that depend on accurate media content delivery or cause reputational damage if content is altered maliciously. Organizations in sectors such as media production, education, or hospitality that use Emby for content distribution may face operational challenges. Additionally, if Emby is integrated into broader IT environments, improper access control could serve as a foothold for further lateral movement or privilege escalation. The medium severity and lack of known exploits reduce immediate risk, but the presence of this vulnerability necessitates timely remediation to prevent future exploitation, especially as attackers often target media servers for unauthorized content manipulation or as entry points into networks.

1. Immediate mitigation should include restricting network access to Emby MediaBrowser servers, limiting exposure to trusted internal networks or VPNs only. 2. Implement strict user privilege management within Emby, ensuring users have only the minimum necessary permissions. 3. Monitor logs for unusual activity related to access control violations or unauthorized changes. 4. Since no patch is currently linked, maintain close communication with Emby for official updates and apply patches promptly once available. 5. Consider deploying Web Application Firewalls (WAF) or network intrusion detection systems to detect and block suspicious access attempts targeting Emby. 6. Conduct regular security audits and penetration testing focusing on access control mechanisms within Emby deployments. 7. Educate administrators on secure configuration best practices for Emby MediaBrowser to prevent misconfigurations that could exacerbate this vulnerability.