CVE-2026-119425

    Dashboard / Vulnerabilities / CVE-2026-119425

    CVE-2026-119425

    Published: 30 Oct 2026Last Modified: 1 Nov 2026

    Summary: OPNsense 26.1.6 through 26.7.7 Captive Portal Session Takeover via Forged ARP

    Details: 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.

    References: https://abraxaslabs.tech/research/opnsense-captive-lastseen-roam, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/119xxx/CVE-2026-119425.json, https://github.com/opnsense/core/security/advisories/GHSA-864r-q4j5-5mjq, https://nvd.nist.gov/vuln/detail/CVE-2026-119425, https://www.vulncheck.com/advisories/opnsense-26.1.6-through-26.7.7-captive-portal-session-takeover-via-forged-arp, https://github.com/opnsense/core/commit/32dc2a3e52eefef5251077f315a0f3243eedb834, https://github.com/opnsense/core/commit/f46836d0c3d14e26d79214009bfbfa9a1eecab55, https://github.com/opnsense/core, https://github.com/opnsense/core/blob/26.7.7/src/opnsense/scripts/captiveportal/cp-background-process.py#L78

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Introduced- e75f212a449838a04a3d6b73596d1e3fcde7d6a7
    Fixed -f46836d0c3d14e26d79214009bfbfa9a1eecab55

    Affected versions

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2026-119425 | CVE-DB