CVE-2021-4477

CRITICAL

9.1

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.

Details CVE

Score CVSS v3.19.1

SeveriteCRITICAL

Vecteur CVSSCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Vecteur d'attaqueNETWORK

ComplexiteLOW

Privileges requisNONE

Interaction utilisateurNONE

Publie4/3/2026

Derniere modification4/3/2026

Sourcenvd

Observations honeypot0

Faiblesses (CWE)

CWE-284

References

https://assets.belden.com/m/5fd1a50fa50cb252/original/Belden-Security-Bulletin-BSECV-1v0-2019-09.pdf(disclosure@vulncheck.com)

https://www.vulncheck.com/advisories/hirschmann-hilcos-openbat-bat450-ipv6-ipsec-firewall-bypass(disclosure@vulncheck.com)

Correlations IOC

Aucune correlation enregistree

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