linux — security advisory
A race condition was found in the Linux kernels implementation of the floppy disk drive controller driver software. The impact of this issue is lessened by the fact that the default permissions on the floppy device (/dev/fd0) are restricted to root. If the permissions on the device have changed the impact changes greatly. In the default configuration root (or equivalent) permissions are required to attack this flaw.
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 4.5.1-1
- CVEs
- CVE-2021-20261
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:57 UTC · Revision 1
Source evidence
A race condition was found in the Linux kernels implementation of the floppy disk drive controller driver software. The impact of this issue is lessened by the fact that the default permissions on the floppy device (/dev/fd0) are restricted to root. If the permissions on the device have changed the impact changes greatly. In the default configuration root (or equivalent) permissions are required to attack this flaw.
osv:DEBIAN-CVE-2021-20261
linux
Fixed versions: 4.5.1-1
linux
Fixed versions: 4.5.1-1
linux
Fixed versions: 4.5.1-1
Complete source record
{
"id": "9dca4783f2b830222e7beabbeb938d6450da4605afac73e6acb0d7c42de8e2fa",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-20261",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-20261",
"summary": "A race condition was found in the Linux kernels implementation of the floppy disk drive controller driver software. The impact of this issue is lessened by the fact that the default permissions on the floppy device (/dev/fd0) are restricted to root. If the permissions on the device have changed the impact changes greatly. In the default configuration root (or equivalent) permissions are required to attack this flaw.",
"evidence": "osv:DEBIAN-CVE-2021-20261",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
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"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
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{
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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:H/PR:H/UI:N/S:U/C:H/I:H/A:H"
}
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"affected": [
{
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"package": {
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"ecosystem": "Debian:12"
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"database_specific": {
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},
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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-2021-20261.json"
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"ecosystem_specific": {
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{
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],
"package": {
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"ecosystem": "Debian:14"
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"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-20261.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:58.898323894Z",
"provider": "osv",
"upstream": [
"CVE-2021-20261"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-20261"
]
},
"related_cves": [
{
"value": "CVE-2021-20261",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 422825,
"published_at": "2021-03-11T21:15:11.983+00:00"
}