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 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.

CVSS v3 9.0 CRITICAL

9.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/opnsense/core/security/advisories/GHSA-872g-g543-j37m
https://github.com/opnsense/core/security/advisories/GHSA-872g-g543-j37m

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-08 23:17

Updated : 2026-09-09 14:17

NVD link : CVE-2026-53581

Mitre link : CVE-2026-53581

CVE.ORG link : CVE-2026-53581

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CWE-73

External Control of File Name or Path

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