CVE-2025-59976 Overview
CVE-2025-59976 is an arbitrary file download vulnerability affecting the web interface of Juniper Networks Junos Space. An authenticated attacker with low privileges can send crafted HTTP GET requests to retrieve files outside the paths normally exposed by the JBoss daemon. Retrieved files may contain sensitive information restricted from low-privileged users, including configuration data and credentials. The flaw is tracked under CWE-552: Files or Directories Accessible to External Parties and affects all versions of Junos Space before 24.1R3. Juniper published details in Security Advisory JSA103170.
Critical Impact
Authenticated network attackers can exfiltrate arbitrary files from the Junos Space filesystem, exposing configuration, credential, and system data that should be restricted.
Affected Products
- Juniper Networks Junos Space, all versions before 24.1R3
- Juniper Junos Space 24.1R1
- Juniper Junos Space 24.1R2
Discovery Timeline
- 2025-10-09 - CVE-2025-59976 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-59976
Vulnerability Analysis
Junos Space is a centralized network management platform for Juniper devices, delivered as a web application hosted on JBoss. The web interface exposes handlers that serve files from defined paths. CVE-2025-59976 stems from insufficient validation of file path parameters passed through GET requests to these handlers.
An authenticated user with low privileges can supply crafted request parameters that traverse beyond the intended directory scope enforced by the JBoss daemon. The application resolves and returns the requested file without confirming the caller is authorized to read it. The result is arbitrary file disclosure limited only by the filesystem permissions of the process serving the request.
Because Junos Space centralizes credentials, device inventories, and administrator sessions, exposed files can include configuration backups, log data, session material, and secrets used to manage downstream Juniper devices.
Root Cause
The root cause is a missing or inadequate access control check on file path input handled by the web interface. The application trusts the requested path and lets the JBoss process access files outside the paths intended for user retrieval. This aligns with [CWE-552], where files intended to be private become reachable through the application interface.
Attack Vector
Exploitation requires network reachability to the Junos Space web interface and valid low-privileged credentials. No user interaction is required. The attacker issues a crafted GET request with a manipulated file identifier or path parameter, and the server returns the requested file content in the HTTP response. The advisory does not describe an unauthenticated path, and public exploit code is not currently available.
Refer to Juniper Security Advisory JSA103170 for vendor-supplied technical detail.
Detection Methods for CVE-2025-59976
Indicators of Compromise
- Anomalous GET requests to Junos Space web endpoints containing path traversal sequences such as ../, encoded variants (%2e%2e%2f), or absolute filesystem paths.
- Successful 200 OK responses from Junos Space serving unusually large or binary payloads to authenticated but low-privileged sessions.
- Access patterns from a single authenticated user enumerating multiple system files (/etc/passwd, JBoss configuration files, keystore paths).
Detection Strategies
- Inspect Junos Space HTTP access logs for GET requests whose parameters contain filesystem path characters or encoded traversal tokens.
- Correlate authenticated Junos Space sessions with request volume and unique file paths accessed to surface enumeration behavior.
- Alert on read attempts against sensitive files (private keys, backup archives, /opt/jboss configuration) originating from the web tier.
Monitoring Recommendations
- Forward Junos Space and JBoss access logs to a centralized SIEM or data lake for retention and query.
- Track authentication events for low-privileged Junos Space accounts and flag sessions producing outbound data volumes inconsistent with role.
- Baseline expected file-serving endpoints and alert on any deviation, particularly requests referencing paths outside the documented web resource tree.
How to Mitigate CVE-2025-59976
Immediate Actions Required
- Upgrade Junos Space to version 24.1R3 or later as directed in JSA103170.
- Restrict network access to the Junos Space web interface to trusted management networks and administrative jump hosts.
- Audit Junos Space accounts, disable unused low-privileged users, and rotate credentials for accounts that may have been abused.
- Review recent web access logs for signs of file download activity matching the indicators listed above.
Patch Information
Juniper has released a fixed build in Junos Space 24.1R3. All prior releases, including 24.1R1 and 24.1R2, are vulnerable. Apply the vendor patch from Juniper Security Advisory JSA103170 following standard change control. There is no partial fix; upgrading is the supported remediation.
Workarounds
- Place the Junos Space web interface behind a reverse proxy or web application firewall that blocks GET parameters containing path traversal sequences and absolute paths.
- Enforce network segmentation so only authorized operators can reach the Junos Space management UI.
- Reduce blast radius by minimizing the number of accounts holding Junos Space access and applying least-privilege role assignments until the upgrade is complete.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
