kubernetes — security advisory
The Kubernetes kubelet component in versions 1.1-1.16.12, 1.17.0-1.17.8 and 1.18.0-1.18.5 do not account for disk usage by a pod which writes to its own /etc/hosts file. The /etc/hosts file mounted in a pod by kubelet is not included by the kubelet eviction manager when calculating ephemeral storage usage by a pod. If a pod writes a large amount of data to the /etc/hosts file, it could fill the storage space of the node and cause the node to fail.
- Products
- kubernetes
- Affected versions
- Not specified
- Fixed versions
- 1.18.5-1
- CVEs
- CVE-2020-8557
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 14:09 UTC · Revision 1
Source evidence
The Kubernetes kubelet component in versions 1.1-1.16.12, 1.17.0-1.17.8 and 1.18.0-1.18.5 do not account for disk usage by a pod which writes to its own /etc/hosts file. The /etc/hosts file mounted in a pod by kubelet is not included by the kubelet eviction manager when calculating ephemeral storage usage by a pod. If a pod writes a large amount of data to the /etc/hosts file, it could fill the storage space of the node and cause the node to fail.
osv:DEBIAN-CVE-2020-8557
kubernetes
Fixed versions: 1.18.5-1
kubernetes
Fixed versions: 1.18.5-1
kubernetes
Fixed versions: 1.18.5-1
Complete source record
{
"id": "cdd206a0ae72425f94f2777f3fecb918386fa48138eb599719ce6fea56c1b423",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-8557",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2020-8557",
"summary": "The Kubernetes kubelet component in versions 1.1-1.16.12, 1.17.0-1.17.8 and 1.18.0-1.18.5 do not account for disk usage by a pod which writes to its own /etc/hosts file. The /etc/hosts file mounted in a pod by kubelet is not included by the kubelet eviction manager when calculating ephemeral storage usage by a pod. If a pod writes a large amount of data to the /etc/hosts file, it could fill the storage space of the node and cause the node to fail.",
"evidence": "osv:DEBIAN-CVE-2020-8557",
"products": [
{
"name": {
"value": "kubernetes",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.18.5-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "kubernetes",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.18.5-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "kubernetes",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1.18.5-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2020-8557",
"aliases": [
"DEBIAN-CVE-2020-8557"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.18.5-1"
}
]
}
],
"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-2020-8557.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.18.5-1"
}
]
}
],
"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-2020-8557.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.18.5-1"
}
]
}
],
"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-2020-8557.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T12:02:51.729827808Z",
"provider": "osv",
"upstream": [
"CVE-2020-8557"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-8557"
]
},
"related_cves": [
{
"value": "CVE-2020-8557",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 453218,
"published_at": "2020-07-23T17:15:12.513+00:00"
}