CVE-2025-46328: Snowflake Connector Race Condition Flaw

CVE-2025-46328 Overview

CVE-2025-46328 is a Time-of-Check Time-of-Use (TOCTOU) race condition vulnerability in the snowflake-connector-nodejs, the official Node.js driver for Snowflake. The vulnerability affects the Easy Logging feature on Linux and macOS platforms, where the driver reads logging configuration from a user-provided file. While the driver attempts to verify that the configuration file can only be written to by its owner, this security check is vulnerable to a TOCTOU race condition and fails to verify that the file owner matches the user running the Driver.

This vulnerability could allow a local attacker with write access to the configuration file or its parent directory to exploit the race window and overwrite the configuration, potentially gaining control over logging level and output location. This could lead to information disclosure, log injection, or further attack escalation.

Critical Impact

Local attackers can exploit the TOCTOU race condition to hijack logging configuration, potentially redirecting sensitive log output or manipulating logging behavior on affected Linux and macOS systems.

Affected Products

• snowflake-connector-nodejs versions 1.10.0 to before 2.0.4
• Snowflake Node.js Connector on Linux platforms
• Snowflake Node.js Connector on macOS platforms

Discovery Timeline

• 2025-04-28 - CVE CVE-2025-46328 published to NVD
• 2025-05-09 - Last updated in NVD database

Technical Details for CVE-2025-46328

Vulnerability Analysis

The vulnerability exists in the file validation logic of the Easy Logging feature within the snowflake-connector-nodejs driver. When the driver initializes logging, it reads configuration from a user-specified file and performs a security check to ensure the file is only writable by its owner. However, this check suffers from two critical flaws:

1. Race Condition Window: The time gap between checking the file permissions (Time-of-Check) and actually using the file contents (Time-of-Use) creates a window where an attacker can swap or modify the configuration file.

2. Incomplete Owner Verification: The original check only verified write permissions but failed to confirm that the file owner matches the user executing the driver, allowing files owned by other users to potentially be used.

Root Cause

The root cause is a classic TOCTOU (CWE-367) vulnerability in the file permission validation logic. The driver performs a non-atomic sequence of operations: first checking file permissions, then separately reading and using the file contents. This non-atomic approach allows an attacker to modify the file between the permission check and the actual file read operation.

Attack Vector

The attack requires local access to the system where the vulnerable Snowflake Node.js connector is running. An attacker would need write access to either the logging configuration file or the directory containing it. The attack scenario involves:

1. Monitoring for when the target application initializes the Snowflake connector
2. Exploiting the race window between the permission check and file use
3. Swapping or modifying the configuration file during this window
4. Gaining control over logging output location and verbosity level

// Security patch in lib/file_util.js - SNOW-1156037: CVE-2025-46328 (#1062)
 const crypto = require('crypto');
 const fs =  require('fs');
+const fsPromises = require('node:fs/promises');
 const path = require('path');
 const struct = require('python-struct');
 const zlib = require('zlib');

Source: GitHub Commit Update

Detection Methods for CVE-2025-46328

Indicators of Compromise

• Unexpected changes to Snowflake connector logging configuration files
• Logging output redirected to unusual or world-readable locations
• Rapid file modification timestamps on logging configuration files suggesting race condition exploitation attempts
• Presence of symbolic links in logging configuration directories that weren't previously authorized

Detection Strategies

• Monitor file system events for rapid modifications to Snowflake logging configuration files using auditd or file integrity monitoring tools
• Implement alerts for unexpected changes in logging output destinations or file ownership changes on configuration files
• Review application logs for anomalous logging behavior patterns that may indicate configuration tampering
• Scan dependency manifests for vulnerable versions of snowflake-connector-nodejs (versions 1.10.0 to before 2.0.4)

Monitoring Recommendations

• Enable file integrity monitoring (FIM) on Snowflake connector configuration directories
• Configure audit rules to track access and modifications to logging configuration files
• Implement runtime application self-protection (RASP) to detect race condition exploitation attempts
• Regularly audit Node.js dependencies using npm audit or similar tools to identify vulnerable connector versions

How to Mitigate CVE-2025-46328

Immediate Actions Required

• Upgrade snowflake-connector-nodejs to version 2.0.4 or later immediately
• Review logging configuration files for any unauthorized modifications
• Audit file permissions and ownership on logging configuration directories
• Implement strict file system permissions to limit write access to configuration directories

Patch Information

This vulnerability has been patched in snowflake-connector-nodejs version 2.0.4. The fix introduces atomic file operations using Node.js fsPromises API and adds proper verification of file ownership to prevent race condition exploitation. Organizations should update their dependencies via npm:

npm update snowflake-sdk@2.0.4

The patch commit is available at the GitHub Commit Update. For additional details, see the GitHub Security Advisory GHSA-wmjq-jrm2-9wfr.

Workarounds

• Restrict write access to logging configuration files and parent directories to only the user running the application
• Ensure configuration files are owned by the same user that runs the Snowflake connector
• Consider disabling the Easy Logging feature if not required until the patch can be applied
• Implement additional file system hardening using immutable attributes where supported

# Configuration example - Secure file permissions for logging configuration
# Ensure configuration file is owned by application user and not world-writable
chown app_user:app_group /path/to/snowflake/log/config.json
chmod 600 /path/to/snowflake/log/config.json

# Set immutable attribute to prevent modifications (requires root)
chattr +i /path/to/snowflake/log/config.json