CVE-2025-46326 is a vulnerability identified in the snowflake-connector-net, which is the official Snowflake Connector for .NET applications. This vulnerability affects versions from 2.1.2 up to, but not including, 4.4.1. The issue is a Time-of-Check to Time-of-Use (TOCTOU) race condition classified under CWE-367. Specifically, when the Easy Logging feature is enabled on Linux and macOS platforms, the connector reads its logging configuration from a user-supplied file. The connector attempts to verify that this configuration file is writable only by its owner to prevent unauthorized modifications. However, the verification process is flawed due to the TOCTOU race condition, where the state of the file can change between the time it is checked and the time it is used. Additionally, the connector fails to confirm that the file owner matches the user running the connector process. This gap allows a local attacker who has write access to the configuration file or the directory containing it to exploit the race condition by replacing or modifying the configuration file after the check but before use. By doing so, the attacker can manipulate the logging level and redirect logging output to arbitrary locations, potentially enabling information disclosure or facilitating further local attacks. The vulnerability does not directly allow privilege escalation or remote code execution but can be leveraged in a local attack scenario to influence application behavior. The issue has been addressed and patched in version 4.4.1 of the connector. The CVSS v3.1 base score is 3.3, reflecting a low severity rating, with the attack vector being local (AV:L), requiring low privileges (PR:L), no user interaction (UI:N), and impacting confidentiality slightly (C:L) but not integrity or availability.

For European organizations using the snowflake-connector-net on Linux or macOS environments, this vulnerability presents a risk primarily in multi-user or shared system contexts where local attackers may have write access to directories or files used by the connector. The impact is limited to potential unauthorized modification of logging configurations, which could lead to information leakage through redirected logs or manipulation of log verbosity, potentially obscuring malicious activities. While the direct impact on data integrity and availability is minimal, the ability to control logging output could aid attackers in maintaining persistence or evading detection. Organizations with strict compliance and auditing requirements may find this particularly concerning, as tampered logs can undermine forensic investigations. However, since exploitation requires local access and write permissions, the threat is less critical for single-user or well-isolated environments. European enterprises relying heavily on Snowflake for data warehousing and analytics, especially those operating in regulated sectors such as finance, healthcare, or government, should consider the implications of compromised logging integrity on their security posture and compliance obligations.

To mitigate this vulnerability, European organizations should prioritize upgrading the snowflake-connector-net to version 4.4.1 or later, where the TOCTOU race condition has been fixed. Beyond patching, organizations should implement strict file system permissions and access controls to limit write access to the logging configuration files and their parent directories only to trusted users and processes. Employing mandatory access control (MAC) frameworks such as SELinux or AppArmor on Linux systems can further restrict unauthorized file modifications. Regularly auditing file permissions and monitoring for unexpected changes to logging configuration files can help detect attempted exploitation. Additionally, running the connector under dedicated, least-privileged service accounts reduces the risk surface. For environments where upgrading is delayed, disabling the Easy Logging feature or configuring logging through alternative secure methods can serve as a temporary workaround. Finally, integrating log integrity verification tools and centralized logging solutions with tamper-evident features can help maintain trustworthiness of logs even if local files are compromised.