linux — security advisory
In the Linux kernel, the following vulnerability has been resolved: neighbour: allow NUD_NOARP entries to be forced GCed IFF_POINTOPOINT interfaces use NUD_NOARP entries for IPv6. It's possible to fill up the neighbour table with enough entries that it will overflow for valid connections after that. This behaviour is more prevalent after commit 58956317c8de ("neighbor: Improve garbage collection") is applied, as it prevents removal from entries that are not NUD_FAILED, unless they are more than 5s old.
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 5.10.46-1
- CVEs
- CVE-2021-47109
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 01:12 UTC · Revision 1
Source evidence
In the Linux kernel, the following vulnerability has been resolved: neighbour: allow NUD_NOARP entries to be forced GCed IFF_POINTOPOINT interfaces use NUD_NOARP entries for IPv6. It's possible to fill up the neighbour table with enough entries that it will overflow for valid connections after that. This behaviour is more prevalent after commit 58956317c8de ("neighbor: Improve garbage collection") is applied, as it prevents removal from entries that are not NUD_FAILED, unless they are more than 5s old.
osv:DEBIAN-CVE-2021-47109
linux
Fixed versions: 5.10.46-1
linux
Fixed versions: 5.10.46-1
linux
Fixed versions: 5.10.46-1
Complete source record
{
"id": "2418a205e990ec9cbd516f7b14ce6349ac20c86fc10933002bb378123f226d4d",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-47109",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-47109",
"summary": "In the Linux kernel, the following vulnerability has been resolved: neighbour: allow NUD_NOARP entries to be forced GCed IFF_POINTOPOINT interfaces use NUD_NOARP entries for IPv6. It's possible to fill up the neighbour table with enough entries that it will overflow for valid connections after that. This behaviour is more prevalent after commit 58956317c8de (\"neighbor: Improve garbage collection\") is applied, as it prevents removal from entries that are not NUD_FAILED, unless they are more than 5s old.",
"evidence": "osv:DEBIAN-CVE-2021-47109",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "5.10.46-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
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],
"severity": "medium",
"structured": {
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"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
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"affected": [
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"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47109.json"
},
"ecosystem_specific": {
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}
},
{
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],
"package": {
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"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47109.json"
},
"ecosystem_specific": {
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},
{
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],
"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47109.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:04:18.549131038Z",
"provider": "osv",
"upstream": [
"CVE-2021-47109"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-47109"
]
},
"related_cves": [
{
"value": "CVE-2021-47109",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 423296,
"published_at": "2024-03-15T21:15:06.457+00:00"
}