CVE-2026-53581: OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.9 of opnsense/core and version 26.4_20 of BE/opnsense/core, a path traversal…

PriorityP357critical9CVSS 3.1

AVNACLPRHUINSCCHILAH

EPSS

0.33%

25.9th percentile

OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.9 of opnsense/core and version 26.4_20 of BE/opnsense/core, a path traversal vulnerability in the NTP configuration module allows an attacker to overwrite arbitrary files on the system as the root user. By manipulating the GPS or PPS serial port parameter, an attacker with access to the NTP configuration can escape the intended directory and force the system to write user-controlled data to any file on the filesystem. Version 26.1.9 of opnsense/core and version 26.4_20 of BE/opnsense/core patch the issue.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
opnsense	core	< 26.1.9	26.1.9
opnsense	core	< 26.4_20	26.4_20

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