CVE-2026-25108: Soliton Systems K.K FileZen OS Command Injection Vulnerability

This vulnerability affects Soliton Systems K.K FileZen and allows an authenticated user to trigger operating system command execution by sending a specially crafted HTTP request after login. The issue stems from insufficient validation of input that reaches system command execution paths, which can give an attacker a foothold inside the environment that hosts the product.

How it works

The weakness is classified as CWE-78, improper neutralization of special elements used in an OS command. After successful authentication, an attacker supplies crafted data inside an HTTP request that the application passes to an underlying operating system command without adequate escaping or filtering.

• The product executes the resulting command in the context of the FileZen process.
• Successful abuse can lead to arbitrary command execution on the host.
• Details of the exact request format and parameters are not provided in the available summary and must be confirmed against the vendor advisory.

Am I affected? How to find it in your systems

FileZen is a file-transfer and management product that may be deployed on premises or as a cloud service. Begin by inventorying all instances through configuration management databases, network scans for known service ports, or application directories that contain FileZen binaries and configuration files.

• Compare installed versions and configurations against the vendor advisory to determine exposure.
• Review authentication and HTTP request logs for entries that originate from authenticated sessions and contain unexpected characters or parameters in fields that reach command execution paths.
• Confirm applicability of any cloud-hosted instances against BOD 22-01 guidance referenced by CISA.

How to remediate

Apply the mitigations or update supplied by the vendor as the primary action. The advisory is the authoritative source for the exact remediation steps and any required configuration changes.

• After applying the vendor update, verify that the vulnerable code paths are no longer reachable.
• Re-audit authentication and input-handling settings to ensure they align with the corrected version.

If you can't patch immediately

Until the vendor fix can be applied, reduce exposure through network segmentation that limits inbound access to FileZen instances to only trusted administrative networks. Consider virtual patching or request filtering at a web application firewall layer for the affected endpoints, and monitor logs for anomalous authenticated HTTP traffic. If mitigations cannot be implemented, discontinue use of the product as stated in the CISA guidance.

If your data may have been exposed

Actively exploited command-injection vulnerabilities have led to unauthorized access and data exposure in other products. Organizations can run a free exposure scan of their email addresses against known breach data to check for prior incidents involving their domains.