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TI-2026-38642 Aliases CVE-2026-53581

ntp: write path traversal

Priority HIGH 72CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · Low · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00473 41st percentileScored 2026-11-07
Fix Fixed core (opnsense): 26.1.9, 26.4_20

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
opnsensecorebefore 26.1.9; before 26.4_2026.1.9, 26.4_20Patch availableCNA
  • core Vendoropnsense Affected before 26.1.9; before 26.4_20 Fixed in 26.1.9, 26.4_20 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*——opnsense
  • cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:* Versions — — ·opnsense

Remediation

  • Fix · CNA core (opnsense) Fixed in 26.1.9, 26.4_20

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-53581

References

Other 1

  • TI-2023-20247 A command injection vulnerability in the component /api/cron/settings/setJob/ of OPNsense… CVSS 3.1CRITICAL 9.8
  • TI-2023-20243 Insecure permissions in the configuration directory (/conf/) of OPNsense Community… CVSS 3.1CRITICAL 9.8
  • TI-2023-20240 A command injection vulnerability in the component diag_backup.php of OPNsense Community… CVSS 3.1CRITICAL 9.8
  • TI-2023-11947 DECISO OPNsense 23.1 does not impose rate limits for authentication, allowing attackers… CVSS 3.1CRITICAL 9.8
  • TI-2026-74819 Path traversal in OPNsense GeoIP importer allows root code execution CVSS 3.1CRITICAL 9.9
  • TI-2023-20246 /ui/cron/item/open in the Cron component of OPNsense Community Edition before 23.7 and… CVSS 3.1CRITICAL 9.6
See all 54 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences