CVE-2025-46619 is a high-severity vulnerability affecting Couchbase Server versions prior to 7.6.4 and 7.2.7 on Windows platforms. The flaw allows unauthorized access to sensitive system files such as /etc/passwd or /etc/shadow, which are critical for user authentication and system security on Unix-like systems. The vulnerability arises due to improper access control (CWE-284), where privilege checks are insufficient or bypassable, enabling an attacker with some level of privileges (PR:L - low privileges) to escalate access to sensitive files without user interaction (UI:N). The CVSS 3.1 score of 7.6 reflects a network attack vector (AV:N), low attack complexity (AC:L), and significant impact on confidentiality (C:H), with limited integrity (I:L) and availability (A:L) impacts. Exploitation does not require user interaction, increasing the risk. Although no known exploits are currently in the wild, the vulnerability's nature suggests that attackers could leverage it to gain sensitive credential information, potentially leading to further system compromise or lateral movement within affected environments. The fix is available in Couchbase Server versions 7.6.4 and 7.2.7 for Windows, emphasizing the need for timely patching.

For European organizations, this vulnerability poses a significant risk, especially for those relying on Couchbase Server for critical applications and data storage. Unauthorized access to files like /etc/passwd or /etc/shadow can lead to credential theft, privilege escalation, and subsequent compromise of sensitive data or systems. This can disrupt business operations, lead to data breaches under GDPR regulations, and cause reputational damage. Organizations in sectors such as finance, healthcare, and government, where data sensitivity and regulatory compliance are paramount, are particularly vulnerable. The network-based attack vector means that attackers can exploit this remotely, increasing the threat surface. Additionally, the potential for lateral movement within networks after initial exploitation can amplify the impact, making containment and remediation more challenging.

European organizations should prioritize upgrading Couchbase Server installations to version 7.6.4 or 7.2.7 (Windows) immediately to remediate this vulnerability. Beyond patching, organizations should implement strict access controls and network segmentation to limit exposure of Couchbase servers to untrusted networks. Monitoring and logging access to sensitive files and Couchbase server activities should be enhanced to detect anomalous behavior indicative of exploitation attempts. Employing host-based intrusion detection systems (HIDS) can help identify unauthorized file access. Additionally, organizations should review and minimize privileges granted to Couchbase service accounts to adhere to the principle of least privilege, reducing the risk of privilege escalation. Regular vulnerability scanning and penetration testing focused on Couchbase deployments can help identify residual risks. Finally, ensure incident response plans include scenarios involving database server compromise to enable swift containment and recovery.