CVE-2025-36225 Overview
CVE-2025-36225 is an information disclosure vulnerability in IBM Aspera Faspex versions 5.0.0 through 5.0.13.1. The flaw allows an authenticated user to infer sensitive information about the underlying system through an observable discrepancy in server responses. This weakness maps to [CWE-203], Observable Discrepancy, where differences in application output reveal data that should remain hidden. IBM published a support bulletin addressing the issue, and the CVE was added to the National Vulnerability Database on October 9, 2025.
Critical Impact
An authenticated attacker can extract sensitive user or system information by analyzing variations in application responses, aiding reconnaissance for follow-on attacks.
Affected Products
- IBM Aspera Faspex versions 5.0.0 through 5.0.13.1
- Deployments on Linux kernel platforms
- Deployments on Microsoft Windows platforms
Discovery Timeline
- 2025-10-09 - CVE-2025-36225 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-36225
Vulnerability Analysis
IBM Aspera Faspex is a managed file transfer product used to exchange large data sets across organizations. CVE-2025-36225 arises because the application returns responses that differ in observable ways depending on the state of internal data. An authenticated user who submits crafted requests can compare these responses and infer sensitive user information from the system.
The issue is categorized as [CWE-203] Observable Discrepancy. Attacks exploiting this class of weakness typically rely on side-channel signals such as differing error messages, response bodies, HTTP status codes, or response timing. The confidentiality impact is limited to information exposure; the flaw does not directly allow modification of data or disruption of service.
Root Cause
The root cause is inconsistent response handling for operations involving user or system data. When the underlying data varies, the application produces distinguishable outputs instead of returning uniform responses. This behavior lets an attacker map response patterns to the presence, absence, or attributes of specific records.
Attack Vector
Exploitation requires network access to the Faspex web interface and valid authenticated credentials with low privileges. No user interaction is needed. The attacker issues a series of API or web requests and analyzes response differences to deduce protected information. Because access is authenticated, the vector is most relevant in environments where Faspex is exposed to a broad user base, contractors, or external partners.
No public proof-of-concept exploit or entry in the CISA Known Exploited Vulnerabilities catalog has been published for CVE-2025-36225. See the IBM Support advisory for vendor technical details.
Detection Methods for CVE-2025-36225
Indicators of Compromise
- Repeated authenticated requests to the same Faspex endpoint with small, iterative variations in parameters such as usernames, package IDs, or resource identifiers.
- Unusual volumes of low-privilege API calls followed by targeted requests against specific accounts or resources.
- Access log entries showing enumeration patterns from a single session over short time windows.
Detection Strategies
- Baseline normal request volumes per authenticated user and alert on statistical anomalies against Faspex API endpoints.
- Correlate authentication events with subsequent enumeration-like request sequences to identify reconnaissance behavior.
- Inspect web server and application logs for repeated requests that differ only in a single parameter value.
Monitoring Recommendations
- Forward Faspex application, web server, and host logs to a centralized analytics platform for retention and correlation.
- Monitor for authenticated sessions performing high-cardinality lookups against user or package resources.
- Track outbound data volumes per session to detect systematic harvesting of inferred information.
How to Mitigate CVE-2025-36225
Immediate Actions Required
- Inventory all IBM Aspera Faspex deployments and confirm versions between 5.0.0 and 5.0.13.1.
- Apply the fixed release published by IBM in the Aspera Faspex security bulletin.
- Rotate credentials for any low-privilege accounts that may have been used for reconnaissance during the exposure window.
- Restrict Faspex administrative and API endpoints to trusted network segments where feasible.
Patch Information
IBM has released an update addressing CVE-2025-36225. Administrators should review the IBM Support page for the fixed version and follow IBM's documented upgrade procedure. Verify the running version after upgrade to confirm remediation of the affected 5.0.0 through 5.0.13.1 range.
Workarounds
- Enforce least-privilege account provisioning and remove unused Faspex user accounts to reduce the authenticated attack surface.
- Place Faspex behind a reverse proxy or web application firewall configured to rate-limit repeated authenticated requests.
- Enable multi-factor authentication for all Faspex users to raise the cost of credential-based access.
- Restrict network exposure of the Faspex service to VPN or IP-allowlisted ranges until patching is complete.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.