GHSA-48x9-g485-9vgwMediumCVSS 5.4
OPNsense core 26.1.6 through 26.7.7 contains an authentication bypass vulnerability in the...
🔗 CVE IDs covered (1)
📋 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.
🔗 References (9)
- https://github.com/opnsense/core/security/advisories/GHSA-864r-q4j5-5mjq
- https://nvd.nist.gov/vuln/detail/CVE-2026-119425
- https://github.com/opnsense/core/commit/32dc2a3e52eefef5251077f315a0f3243eedb834
- https://github.com/opnsense/core/commit/f46836d0c3d14e26d79214009bfbfa9a1eecab55
- https://abraxaslabs.tech/research/opnsense-captive-lastseen-roam
- https://github.com/opnsense/core
- https://github.com/opnsense/core/blob/26.7.7/src/opnsense/scripts/captiveportal/cp-background-process.py#L78
- https://www.vulncheck.com/advisories/opnsense-26.1.6-through-26.7.7-captive-portal-session-takeover-via-forged-arp
- https://github.com/advisories/GHSA-48x9-g485-9vgw