kubernetes — security advisory
As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.
- Products
- kubernetes
- Affected versions
- Not specified
- Fixed versions
- 1.20.5+really1.20.2-1
- CVEs
- CVE-2020-8562
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 13:37 UTC · Revision 1
Source evidence
As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.
osv:DEBIAN-CVE-2020-8562
kubernetes
Fixed versions: 1.20.5+really1.20.2-1
kubernetes
Fixed versions: 1.20.5+really1.20.2-1
kubernetes
Fixed versions: 1.20.5+really1.20.2-1
Complete source record
{
"id": "b5205893de857af68c04dc6de4c85c236f1ec2b2d5a8262aa539ffc4c8678eae",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-8562",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2020-8562",
"summary": "As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.",
"evidence": "osv:DEBIAN-CVE-2020-8562",
"products": [
{
"name": {
"value": "kubernetes",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.20.5+really1.20.2-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "kubernetes",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.20.5+really1.20.2-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "kubernetes",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.20.5+really1.20.2-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "low",
"structured": {
"id": "DEBIAN-CVE-2020-8562",
"aliases": [
"DEBIAN-CVE-2020-8562"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.20.5+really1.20.2-1"
}
]
}
],
"package": {
"name": "kubernetes",
"purl": "pkg:deb/debian/kubernetes?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-8562.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.20.5+really1.20.2-1"
}
]
}
],
"package": {
"name": "kubernetes",
"purl": "pkg:deb/debian/kubernetes?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-8562.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.20.5+really1.20.2-1"
}
]
}
],
"package": {
"name": "kubernetes",
"purl": "pkg:deb/debian/kubernetes?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-8562.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T12:02:33.579370364Z",
"provider": "osv",
"upstream": [
"CVE-2020-8562"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-8562"
]
},
"related_cves": [
{
"value": "CVE-2020-8562",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 452612,
"published_at": "2022-02-01T11:15:10.903+00:00"
}