Critical
Security advisory
In strongSwan before 5.9.5, a malicious responder can send an EAP-Success message too early without actually authenticating the client and (in the case of EAP methods with mutual authentication and EAP-only authentication for IKEv2) even without server authentication.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-45079
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 04:35 UTC · Revision 1
Source evidence
In strongSwan before 5.9.5, a malicious responder can send an EAP-Success message too early without actually authenticating the client and (in the case of EAP methods with mutual authentication and EAP-only authentication for IKEv2) even without server authentication.
osv:CVE-2021-45079
Complete source record
{
"id": "bfc9f36041c67d0b8ca03a10186c22d587e64e658b094030e6a8b1e66cd16926",
"url": "https://osv.dev/vulnerability/CVE-2021-45079",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-45079",
"summary": "In strongSwan before 5.9.5, a malicious responder can send an EAP-Success message too early without actually authenticating the client and (in the case of EAP methods with mutual authentication and EAP-only authentication for IKEv2) even without server authentication.",
"evidence": "osv:CVE-2021-45079",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2021-45079",
"aliases": [
"CVE-2021-45079"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/strongswan/strongswan",
"type": "GIT",
"events": [
{
"introduced": "5fc278edf3795ce7eb2ff11195797f481ede0d77"
},
{
"fixed": "57d6e96943ae583367ae47e08edf1c43013f1bdc"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:strongswan:strongswan:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.1.2"
},
{
"fixed": "5.9.5"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
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"5.9.5dr4",
"5.9.5dr3",
"5.9.5dr2",
"5.9.5dr1",
"5.9.4",
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"5.9.4dr3",
"5.9.4dr2",
"5.9.4dr1",
"android-2.3.3-1",
"android-2.3.3",
"5.9.3",
"5.9.3rc1",
"5.9.3dr4",
"5.9.3dr3",
"5.9.3dr2",
"5.9.3dr1",
"5.9.2",
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"5.9.2rc1",
"5.9.2dr2",
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"5.8.1",
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"5.8.0dr2",
"5.7.2",
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"5.7.2dr4",
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"5.7.2dr1",
"5.7.1",
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"5.7.0dr6",
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"5.7.0dr2",
"5.7.0dr1",
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"5.5.3",
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"5.5.2",
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"5.5.2dr7",
"5.5.2dr6",
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"5.4.0dr4",
"5.4.0dr3",
"5.4.0dr2",
"5.4.0dr1",
"5.3.5",
"5.3.4",
"5.3.4rc1",
"5.3.4dr3",
"5.3.4dr2",
"5.3.4dr1",
"5.3.3",
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"5.3.3dr6",
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"5.3.2",
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"5.0.2dr4",
"5.0.1",
"5.0.0",
"4.6.3",
"4.6.2",
"4.6.1",
"4.6.0",
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"4.5.2",
"4.5.1",
"4.5.0",
"4.4.1",
"4.3.6",
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"4.3.4",
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"4.1.4",
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],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-45079.json"
}
}
],
"modified": "2026-10-24T10:30:20.529663499Z",
"provider": "osv",
"references": [
"https://www.strongswan.org/blog/2022/01/24/strongswan-vulnerability-%28cve-2021-45079%29.html"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*",
"cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*",
"cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*",
"cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*",
"cpe:2.3:o:canonical:ubuntu_linux:21.10:*:*:*:*:*:*:*"
],
"vendor_product": "canonical:ubuntu_linux",
"extracted_events": [
{
"range": [
{
"introduced": "14.04"
},
{
"last_affected": "14.04"
},
{
"introduced": "16.04"
},
{
"last_affected": "16.04"
},
{
"introduced": "18.04"
},
{
"last_affected": "18.04"
},
{
"introduced": "20.04"
},
{
"last_affected": "20.04"
},
{
"introduced": "21.10"
},
{
"last_affected": "21.10"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
"cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "9.0"
},
{
"last_affected": "9.0"
},
{
"introduced": "10.0"
},
{
"last_affected": "10.0"
},
{
"introduced": "11.0"
},
{
"last_affected": "11.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:7.0:*:*:*:*:*:*:*",
"cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:8.0:*:*:*:*:*:*:*",
"cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:9.0:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:extra_packages_for_enterprise_linux",
"extracted_events": [
{
"range": [
{
"introduced": "7.0"
},
{
"last_affected": "7.0"
},
{
"introduced": "8.0"
},
{
"last_affected": "8.0"
},
{
"introduced": "9.0"
},
{
"last_affected": "9.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "34"
},
{
"last_affected": "34"
},
{
"introduced": "35"
},
{
"last_affected": "35"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-45079",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 430294,
"published_at": "2022-01-31T08:15:07.307+00:00"
}