CVE-2025-49015: 
C# vulnerability analysis and mitigation

The Couchbase .NET SDK (client library) before version 3.7.1 contains a security vulnerability related to TLS certificate validation. The vulnerability stems from improper hostname verification for TLS certificates, and additionally, the SDK was using IP addresses instead of hostnames due to a configuration option that was incorrectly enabled by default (NVD, Wiz).

The vulnerability is classified as CWE-297 (Improper Validation of Certificate with Host Mismatch). It has been assigned a CVSS v3.1 base score of 4.9 (MEDIUM) with the following vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N. The issue specifically involves the SDK not properly enabling hostname verification for TLS certificates, while also using IP addresses instead of hostnames due to an incorrectly enabled default configuration option (Wiz).

The vulnerability could potentially allow attackers to bypass certificate hostname verification, which is a critical security measure in TLS certificate validation. This could lead to unauthorized access to confidential information through man-in-the-middle attacks, though the high privilege requirement (PR:H) somewhat mitigates the risk (Wiz).

The vulnerability has been fixed in Couchbase .NET SDK version 3.7.1. Users are advised to upgrade to this version or later to address the security issue. The fix properly enforces hostname verification for TLS certificates and corrects the default configuration for hostname usage (Couchbase Alerts).