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CVE-2021-4477

Hirschmann HiLCOS

Description

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.

CVSS 9.1EPSS 0.319%Risk 0.94
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Published
2026-04-03 23:17:01
Affected versions
unknown
Type
Firmware
Last modified
2026-07-24 22:10:00
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N