CVE-2021-4477 — Hirschmann HiLCOS OpenBAT BAT450 IPv6 IPsec Firewall Bypass
Hirschmann HiLCOS OpenBAT and BAT450 products contain a firewall bypass vulnerability in IPv6 IPsec deployments that allows traffic from VPN connections to bypass configured fir…
Published: 2026-04-03 · CVSS: 9.3 · CVSS 4.0
Hirschmann HiLCOS OpenBAT and BAT450 products contain a firewall bypass vulnerability in IPv6 IPsec deployments that allows traffic from VPN connections to bypass configured firewall rules. Attackers can exploit this vulnerability by establishing IPv6 IPsec connections (IKEv1 or IKEv2) while simultaneously using an IPv6 Internet connection to circumvent firewall policy enforcement.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7