by Kastro
Paper/Archive/CVE-2021-4477

CVE-2021-4477

Belden Hirschmann HiLCOS OpenBAT — Hirschmann HiLCOS OpenBAT BAT450 IPv6 IPsec Firewall Bypass

EPSS 0.3%CVSS 9.3
critical.is priorityof 100
33
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 26.4.264 × 205.3No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Hirschmann HiLCOS OpenBAT3.80-REL–CNA
Hirschmann HiLCOS OpenBAT8.90-REL–CNA
Hirschmann HiLCOS OpenBAT9.00-REL–CNA
Hirschmann HiLCOS OpenBAT9.00-RU1–CNA
Hirschmann HiLCOS OpenBAT9.10-REL–CNA
Hirschmann HiLCOS OpenBAT9.12-REL–CNA
Hirschmann HiLCOS OpenBAT9.12-RU1–CNA
Hirschmann HiLCOS OpenBAT9.12-RU2–CNA
Hirschmann HiLCOS OpenBAT9.12-RU3–CNA
Hirschmann HiLCOS OpenBAT9.12-RU4–CNA
Hirschmann HiLCOS OpenBAT9.12-RU5–CNA
Hirschmann HiLCOS OpenBAT9.12-RU6–CNA

Scores by source

VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
VulnCheck (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

advisoryassets.belden.com/m/5fd1a50fa50cb252/original/Belden-Security-Bulletin-BSECV-1v0-2019-09.pdfrefvulncheck.com/advisories/hirschmann-hilcos-openbat-bat450-ipv6-ipsec-firewall-bypass