Cilium vulnerable to potential network policy bypass when routing IPv6 traffic
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.11.15, 1.12.8, and 1.13.1, under specific conditions, Cilium may misattribute the source IP address of traffic to a cluster, identifying external traffic as coming from the host on which Cilium is running. As a consequence, network policies for that cluster might be bypassed, depending on the specific network policies enabled. This issue only manifests when Cilium is routing IPv6 traffic and NodePorts are used to route traffic to pods. IPv6 and endpoint routes are both disabled by default. The problem has been fixed and is available on versions 1.11.15, 1.12.8, and 1.13.1. As a workaround, disable IPv6 routing.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2023-27594
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 2 Nov 2026, 19:57 UTC · Revision 1
Source evidence
Cilium vulnerable to potential network policy bypass when routing IPv6 traffic
core-osv · Original sourcePublished 17 Mar 2023, 19:56 UTC
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.11.15, 1.12.8, and 1.13.1, under specific conditions, Cilium may misattribute the source IP address of traffic to a cluster, identifying external traffic as coming from the host on which Cilium is running. As a consequence, network policies for that cluster might be bypassed, depending on the specific network policies enabled. This issue only manifests when Cilium is routing IPv6 traffic and NodePorts are used to route traffic to pods. IPv6 and endpoint routes are both disabled by default. The problem has been fixed and is available on versions 1.11.15, 1.12.8, and 1.13.1. As a workaround, disable IPv6 routing.
osv:CVE-2023-27594
Complete source record
{
"id": "02ed7850266d7ac981ecef85e29be33d805f6feb63376f877b5e5b0a3f6ff213",
"url": "https://osv.dev/vulnerability/CVE-2023-27594",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Cilium vulnerable to potential network policy bypass when routing IPv6 traffic",
"summary": "Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.11.15, 1.12.8, and 1.13.1, under specific conditions, Cilium may misattribute the source IP address of traffic to a cluster, identifying external traffic as coming from the host on which Cilium is running. As a consequence, network policies for that cluster might be bypassed, depending on the specific network policies enabled. This issue only manifests when Cilium is routing IPv6 traffic and NodePorts are used to route traffic to pods. IPv6 and endpoint routes are both disabled by default. The problem has been fixed and is available on versions 1.11.15, 1.12.8, and 1.13.1. As a workaround, disable IPv6 routing.",
"evidence": "osv:CVE-2023-27594",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2023-27594",
"aliases": [
"BIT-cilium-2023-27594",
"BIT-cilium-operator-2023-27594",
"BIT-cilium-proxy-2023-27594",
"BIT-hubble-2023-27594",
"BIT-hubble-relay-2023-27594",
"BIT-hubble-ui-2023-27594",
"BIT-hubble-ui-backend-2023-27594",
"CVE-2023-27594",
"GHSA-8fg8-jh2h-f2hc",
"GO-2023-1643"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/cilium/cilium",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "c5577e8e8987ec4355751094f09248fb58734fdc"
},
{
"introduced": "9447cd1bfab4424ccb59b5ea9ca41f89590261d4"
},
{
"fixed": "87d85617d1385ba9cce4c6471c32d7302f2648ab"
},
{
"introduced": "c9723a8df3cfa336da1f8457a864105d8349acfe"
},
{
"fixed": "a6be57eb805dd60c6516c2fe22cddbe1e09c3812"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "1.11.15"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.12.0"
},
{
"fixed": "1.12.8"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.13.0"
},
{
"fixed": "1.13.1"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "c5577e8e8987ec4355751094f09248fb58734fdc"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.11.15"
},
{
"range": [
{
"fixed": "87d85617d1385ba9cce4c6471c32d7302f2648ab"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.12.8"
},
{
"range": [
{
"fixed": "a6be57eb805dd60c6516c2fe22cddbe1e09c3812"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.13.1"
}
]
}
}
],
"versions": [
"v1.13.0",
"1.13.0",
"v1.12.7",
"1.12.7",
"v1.11.14",
"1.11.14",
"v1.12.6",
"1.12.6",
"v1.11.13",
"1.11.13",
"v1.12.5",
"1.12.5",
"v1.11.12",
"1.11.12",
"v1.12.3",
"1.12.3",
"v1.11.11",
"1.11.11",
"v1.12.4",
"1.12.4",
"v1.11.10",
"1.11.10",
"v1.12.2",
"1.12.2",
"v1.11.9",
"1.11.9",
"v1.11.8",
"1.11.8",
"v1.12.1",
"1.12.1",
"v1.12.0",
"1.12.0",
"v1.11.7",
"1.11.7",
"v1.11.6",
"1.11.6",
"v1.11.5",
"1.11.5",
"v1.11.4",
"1.11.4",
"v1.11.3",
"1.11.3",
"v1.11.2",
"1.11.2",
"v1.11.1",
"1.11.1",
"v1.11.0",
"1.11.0",
"v1.11.0-rc3",
"1.11.0-rc3",
"v1.11.0-rc2",
"1.11.0-rc2",
"v1.11.0-rc1",
"1.11.0-rc1",
"v1.11.0-rc0",
"1.11.0-rc0",
"v1.10.0-rc0",
"1.10.0-rc0",
"v1.9.0-rc1",
"1.9.0-rc1",
"v1.9.0-rc0",
"1.9.0-rc0",
"v1.8.0-rc1",
"1.8.0-rc1",
"v1.7.0-rc2",
"v1.7.0-rc1",
"v1.6.0-rc3",
"v1.6.0-rc2",
"v1.6.0-rc1",
"v1.5.0-rc2",
"1.5.0-rc2",
"v1.5.0-rc1",
"v1.3.0-rc1",
"v0.13.25",
"v0.13.22",
"v0.13.21",
"v1.0.0-rc9",
"v0.13.20",
"v0.13.19",
"v0.13.18",
"v0.13.17",
"v0.13.16",
"v0.13.15",
"v1.0.0-rc8",
"v0.13.14",
"v1.0.0-rc7",
"v1.0.0-rc6",
"v0.13.10",
"v0.13.8",
"v1.0.0-rc5",
"v0.13.6",
"v0.13.5",
"v1.0.0-rc4",
"v0.13.4",
"v0.13.2",
"v0.13.1",
"v1.0.0-rc1",
"v0.10.0",
"v0.9.0-rc1",
"v0.8.2",
"v0.8.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-27594.json"
}
}
],
"modified": "2026-10-28T02:30:23.186691525Z",
"provider": "osv",
"references": [
"https://github.com/cilium/cilium/releases/tag/v1.11.15",
"https://github.com/cilium/cilium/releases/tag/v1.12.8",
"https://github.com/cilium/cilium/releases/tag/v1.13.1",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/27xxx/CVE-2023-27594.json",
"https://github.com/cilium/cilium/security/advisories/GHSA-8fg8-jh2h-f2hc",
"https://nvd.nist.gov/vuln/detail/CVE-2023-27594"
],
"provider_metadata": {
"cwe_ids": [
"CWE-285"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/27xxx/CVE-2023-27594.json"
}
},
"related_cves": [
{
"value": "CVE-2023-27594",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 489485,
"published_at": "2023-03-17T19:56:43.687+00:00"
}