CVE-2025-30474: Apache Commons VFS Info Disclosure Flaw

CVE-2025-30474 Overview

CVE-2025-30474 is an Exposure of Sensitive Information to an Unauthorized Actor vulnerability affecting Apache Commons VFS, a popular Java library that provides a single API for accessing various file systems. The vulnerability exists in the FtpFileObject class, which can inadvertently expose sensitive credentials when handling file-not-found exceptions.

When an FTP file operation fails because a file cannot be found, the FtpFileObject class throws an exception containing the original URI in its message. This URI may include the FTP password in plaintext, leading to potential credential exposure through application logs, error messages, or monitoring systems.

Critical Impact

Sensitive FTP credentials including passwords may be exposed through exception messages, potentially enabling unauthorized access to FTP servers and data exfiltration.

Affected Products

• Apache Commons VFS versions before 2.10.0
• Applications using Apache Commons VFS for FTP file operations
• Java applications that log or display exception messages from Commons VFS FTP operations

Discovery Timeline

• 2025-03-23 - CVE-2025-30474 published to NVD
• 2025-07-14 - Last updated in NVD database

Technical Details for CVE-2025-30474

Vulnerability Analysis

This information disclosure vulnerability stems from improper handling of sensitive data within exception messages. Apache Commons VFS provides a unified interface for interacting with various file systems, including FTP, SFTP, HTTP, and local file systems. When users connect to FTP servers, they typically provide credentials in the URI format such as ftp://username:password@hostname/path.

The FtpFileObject class is responsible for handling FTP file operations within the Commons VFS framework. When a requested file is not found on the FTP server, the class generates an exception to notify the calling application. However, versions prior to 2.10.0 included the complete original URI—including the password component—in the exception message.

This behavior becomes a security concern because exception messages are commonly written to application logs, displayed in error pages, captured by monitoring systems, or transmitted to centralized logging infrastructure. Any of these pathways could expose the plaintext password to unauthorized parties.

Root Cause

The root cause of this vulnerability lies in the exception handling logic within the FtpFileObject class. When constructing error messages for file-not-found scenarios, the code did not implement password masking before including the URI in the exception text. The URI object was converted directly to a string representation without sanitizing sensitive authentication parameters.

This oversight in the error handling code path meant that while the application may have been designed to protect credentials during normal operation, the exception pathway created an unintended disclosure vector. The fix implemented in version 2.10.0 ensures that passwords are masked in exception messages before they are propagated.

Attack Vector

The attack vector for this vulnerability is network-based and requires specific conditions to be exploited. An attacker would need to be in a position to observe exception messages generated by applications using vulnerable versions of Apache Commons VFS.

Potential exploitation scenarios include:

1. Log File Access: An attacker with access to application logs could extract FTP credentials from logged exception messages
2. Error Page Exposure: Web applications displaying detailed error messages could inadvertently reveal credentials to end users
3. Monitoring System Compromise: Centralized logging or monitoring systems collecting exception data could become repositories of exposed credentials
4. Debug Output: Development or staging environments with verbose logging enabled may expose credentials more readily

The vulnerability does not require any special privileges beyond the ability to trigger a file-not-found condition and observe the resulting exception message.

Detection Methods for CVE-2025-30474

Indicators of Compromise

• Exception messages or log entries containing FTP URIs with visible password components (e.g., ftp://user:password@host/path)
• Unusual access patterns to FTP servers that may indicate credential theft
• Log files containing plaintext authentication credentials in URI format
• Monitoring alerts for sensitive data patterns in application exception logs

Detection Strategies

• Audit application logs for exception messages containing URI strings with authentication credentials
• Implement log scanning rules to detect patterns matching ftp://[user]:[password]@ in exception output
• Review application dependencies to identify usage of Apache Commons VFS versions prior to 2.10.0
• Use Software Composition Analysis (SCA) tools to inventory vulnerable library versions across your environment

Monitoring Recommendations

• Configure log monitoring to alert on potential credential exposure patterns in exception messages
• Implement Data Loss Prevention (DLP) rules to detect and redact credential patterns in log streams
• Monitor for anomalous FTP access patterns that could indicate compromised credentials
• Establish baseline behaviors for FTP authentication to identify potential unauthorized access

How to Mitigate CVE-2025-30474

Immediate Actions Required

• Upgrade Apache Commons VFS to version 2.10.0 or later immediately
• Audit existing application logs for exposed FTP credentials and rotate any potentially compromised passwords
• Review applications using Apache Commons VFS to ensure proper exception handling that does not expose raw exception messages to end users
• Implement log sanitization to mask credential patterns before storage or transmission

Patch Information

Apache has released version 2.10.0 of Commons VFS which addresses this vulnerability by implementing password masking in exception messages. Users should upgrade to this version or later to remediate the issue.

For detailed information about the fix, refer to the Apache JIRA Ticket VFS-169 and the Apache Mailing List Thread.

Workarounds

• Implement custom exception handlers that sanitize URI strings before logging or displaying exception messages
• Configure logging frameworks to filter or redact patterns matching credential formats in log output
• Avoid including credentials directly in FTP URIs; consider using credential providers or configuration files with appropriate access controls
• Deploy application-level log sanitization to mask sensitive data patterns before persistence

# Maven dependency update example
# Update pom.xml to use the patched version
# Change: <version>2.9.0</version>
# To: <version>2.10.0</version>

# Verify the updated version
mvn dependency:tree | grep commons-vfs