What is CVE-2026-2035?

CVE-2026-2035 is a medium-severity vulnerability in Deciso Opnsense, classified under OS Command Injection. CVSS score: 6.8/10. Published 2026-02-20.

How severe is CVE-2026-2035?

Medium severity. CVSS v3 base score is 6.8 out of 10.

RCE in Deciso Opnsense

CVE-2026-2035

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.

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.015 (72.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.0/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

Affected products

Deciso Opnsense — versions 25.7

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

zdi-disclosures@trendmicro.com (x_research-advisory)
zdi-disclosures@trendmicro.com (vendor-advisory)

Frequently asked questions

What is CVE-2026-2035?: CVE-2026-2035 is a medium-severity vulnerability in Deciso Opnsense, classified under OS Command Injection. CVSS score: 6.8/10. Published 2026-02-20.
How severe is CVE-2026-2035?: Medium severity. CVSS v3 base score is 6.8 out of 10.