Deciso OPNsense diag_backup.php command injection

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Deciso OPNsense. This impacts an unknown function of the file diag_backup.php. The manipulation results in command injection. This vulnerability is reported as CVE-2026-2035. The attack can be launched remotely. No exploit exists. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in Deciso OPNsense (unknown version). Affected is an unknown code block of the file diag_backup.php. The manipulation with an unknown input leads to a command injection vulnerability. CWE is classifying the issue as CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Deciso OPNsense diag_backup.php filename Command Injection Remote Code Execution Vulnerability. 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 string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-28131.

The advisory is available at zerodayinitiative.com. This vulnerability is traded as CVE-2026-2035. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are required for exploitation. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1202 by the MITRE ATT&CK project.

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

Applying the patch cb15c935137d05c86a1e6cf12af877e9c32a23af is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0407). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Open Source OPNsense

Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.9

VulDB Base Score: 7.2
VulDB Temp Score: 6.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.8
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Command injection
CWE: CWE-77 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Google Hack: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: cb15c935137d05c86a1e6cf12af877e9c32a23af

Timelineinfo

02/13/2026 Advisory disclosed
02/13/2026 +0 days VulDB entry created
02/22/2026 +9 days VulDB entry last update

Sourcesinfo

Advisory: zerodayinitiative.com
Status: Confirmed

CVE: CVE-2026-2035 (🔒)
GCVE (CVE): GCVE-0-2026-2035
GCVE (VulDB): GCVE-100-345882
CERT Bund: WID-SEC-2026-0407 - OPNsense: Schwachstelle ermöglicht Ausführen von beliebigem Programmcode mit Administratorrechten

Entryinfo

Created: 02/13/2026 08:08
Updated: 02/22/2026 20:54
Changes: 02/13/2026 08:08 (52), 02/13/2026 10:08 (7), 02/22/2026 20:54 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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