snapd — security advisory
snapd 2.54.2 fails to perform sufficient validation of snap content interface and layout paths, resulting in the ability for snaps to inject arbitrary AppArmor policy rules via malformed content interface and layout declarations and hence escape strict snap confinement. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1
- Products
- snapd
- Affected versions
- Not specified
- Fixed versions
- 2.54.3-1
- CVEs
- CVE-2021-4120
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:44 UTC · Revision 1
Source evidence
snapd 2.54.2 fails to perform sufficient validation of snap content interface and layout paths, resulting in the ability for snaps to inject arbitrary AppArmor policy rules via malformed content interface and layout declarations and hence escape strict snap confinement. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1
osv:DEBIAN-CVE-2021-4120
snapd
Fixed versions: 2.54.3-1
snapd
Fixed versions: 2.54.3-1
snapd
Fixed versions: 2.54.3-1
Complete source record
{
"id": "e44ae92144cb2ea5b21b8be8a9e71f903fd5e904e7312505526afb0e31b076ba",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-4120",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-4120",
"summary": "snapd 2.54.2 fails to perform sufficient validation of snap content interface and layout paths, resulting in the ability for snaps to inject arbitrary AppArmor policy rules via malformed content interface and layout declarations and hence escape strict snap confinement. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1",
"evidence": "osv:DEBIAN-CVE-2021-4120",
"products": [
{
"name": {
"value": "snapd",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.54.3-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "snapd",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.54.3-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "snapd",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.54.3-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2021-4120",
"aliases": [
"DEBIAN-CVE-2021-4120"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.54.3-1"
}
]
}
],
"package": {
"name": "snapd",
"purl": "pkg:deb/debian/snapd?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-4120.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.54.3-1"
}
]
}
],
"package": {
"name": "snapd",
"purl": "pkg:deb/debian/snapd?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-4120.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.54.3-1"
}
]
}
],
"package": {
"name": "snapd",
"purl": "pkg:deb/debian/snapd?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-4120.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:38.675781656Z",
"provider": "osv",
"upstream": [
"CVE-2021-4120"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-4120"
]
},
"related_cves": [
{
"value": "CVE-2021-4120",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 422117,
"published_at": "2022-02-17T23:15:07.55+00:00"
}