Deciso OPNsense diag_backup.php filename Directory Traversal Remote Code Execution Vulnerability
Vulnerability Details
This vulnerability allows network-adjacent attackers to execute arbitrary code 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 execute code in the context of root.
Additional Details
Deciso has issued an update to correct this vulnerability. More details can be found at:
https://github.com/opnsense/core/commit/cb15c935137d05c86a1e6cf12af877e9c32a23af
Disclosure Timeline
- 2025-10-29 - Vulnerability reported to vendor
- 2025-11-25 - Coordinated public release of advisory
- 2026-02-24 - Advisory Updated
Credit
Alex Williams from Pellera Technologies
