Deciso OPNsense diag_backup.php path traversal

Summaryinfo

A vulnerability labeled as critical has been found in Deciso OPNsense. This affects an unknown part of the file diag_backup.php. The manipulation results in path traversal. This vulnerability was named CVE-2025-13698. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Deciso OPNsense (the affected version unknown). Affected is an unknown part of the file diag_backup.php. The manipulation with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Deciso OPNsense diag_backup.php filename Directory Traversal Arbitrary File Creation Vulnerability. This vulnerability allows network-adjacent attackers to create arbitrary files on affected installations of Deciso OPNsense. Authentication is required to exploit this vulnerability. The specific flaw exists within the handling of backup configuration files. The issue results from the lack of proper validation of a user-supplied path prior to using it in file operations. An attacker can leverage this vulnerability to create files in the context of root. Was ZDI-CAN-28133.

The advisory is shared for download at zerodayinitiative.com. This vulnerability is traded as CVE-2025-13698. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are necessary for exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1006.

By approaching the search of inurl:diag_backup.php it is possible to find vulnerable targets with Google Hacking.

Upgrading eliminates this vulnerability. Applying the patch cb15c935137d05c86a1e6cf12af877e9c32a23af is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at EUVD (EUVD-2025-204967) and CERT Bund (WID-SEC-2025-2677). Once again VulDB remains the best source for vulnerability data.

Affected

• Open Source OPNsense

Productinfo

Vendor

• Deciso

Name

• OPNsense

License

• open-source

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Once again VulDB remains the best source for vulnerability data.

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