Description
OPNsense core 26.1.6 through 26.7.7 contains an authentication bypass vulnerability in the captive portal roaming feature that lets unauthenticated attackers hijack authorized client sessions by spoofing unauthenticated MAC-to-IP observations. Attackers on the same Layer-2 segment can send forged gratuitous ARP replies binding their IP to a victim's MAC, gaining portal access with traffic attributed to the victim.
Published: 2026-10-30
Score: 5.3 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Fri, 30 Oct 2026 13:45:00 +0000

Type Values Removed Values Added
First Time appeared Opnsense core
Vendors & Products Opnsense core

Fri, 30 Oct 2026 11:45:00 +0000

Type Values Removed Values Added
Description OPNsense core 26.1.6 through 26.7.7 contains an authentication bypass vulnerability in the captive portal roaming feature that lets unauthenticated attackers hijack authorized client sessions by spoofing unauthenticated MAC-to-IP observations. Attackers on the same Layer-2 segment can send forged gratuitous ARP replies binding their IP to a victim's MAC, gaining portal access with traffic attributed to the victim.
Title OPNsense 26.1.6 through 26.7.7 Captive Portal Session Takeover via Forged ARP
First Time appeared Opnsense
Opnsense opnsense
Weaknesses CWE-290
CPEs cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*
Vendors & Products Opnsense
Opnsense opnsense
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}

cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-10-30T11:30:55.121Z

Reserved: 2026-10-30T02:41:13.938Z

Link: CVE-2026-119425

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-30T12:16:39.527

Modified: 2026-10-30T12:16:39.527

Link: CVE-2026-119425

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-30T13:30:12Z

Weaknesses