CVE-2021-4477 (GCVE-0-2021-4477)
Vulnerability from cvelistv5 – Published: 2026-04-03 22:37 – Updated: 2026-04-06 13:17
VLAI?
Title
Hirschmann HiLCOS OpenBAT BAT450 IPv6 IPsec Firewall Bypass
Summary
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.
Severity ?
9.1 (Critical)
CWE
- CWE-284 - Improper access control
Assigner
References
| URL | Tags | |
|---|---|---|
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Belden | Hirschmann HiLCOS OpenBAT |
Affected:
3.80-REL
(custom)
Affected: 8.90-REL (custom) Affected: 9.00-REL (custom) Affected: 9.00-RU1 (custom) Affected: 9.10-REL (custom) Affected: 9.12-REL (custom) Affected: 9.12-RU1 (custom) Affected: 9.12-RU2 (custom) Affected: 9.12-RU3 (custom) Affected: 9.12-RU4 (custom) Affected: 9.12-RU5 (custom) Affected: 9.12-RU6 (custom) Affected: 9.12-RU7 (custom) Affected: 9.12-RU8 (custom) Affected: 9.12-RU9 (custom) Affected: 9.13-REL (custom) Affected: 9.13-RU1 (custom) Affected: 10.12-REL (custom) Affected: 10.12-RU1 (custom) Unaffected: 10.12-RU2 (custom) |
Date Public ?
2021-01-11 00:00
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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