CVE-2021-4120

mediumpriority · track · 31EPSS 0.004 · 38 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.44% (38th) EPSS

CVSS 4.6 · medium

Is it mine?

9 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

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

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–8.8

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.18.8highAV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.2highCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Hsecondary · ENISA EU

v3.18.2highCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Hsecondary · security@ubuntu.comexploitability 1.5 · impact 6

v3.17.1highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20US

affected products (9)

Products and version ranges known to be affected.

Canonical Ltd. snapd≤ unspecified ≤2.54.2enisa_euvdEU
Canonical Ltd. snapd≤ 2.54.2fstec_bduRU
ООО «Ред Софт» РЕД ОС≤ 7.3fstec_bduRU
canonical snapd≤ 2.54.2nvdUScpe:2.3:a:canonical:snapd:*:*:*:*:*:*:*:*
canonical ubuntu linux= 18.04nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
canonical ubuntu linux= 20.04nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
canonical ubuntu linux= 21.10nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
fedoraproject fedora= 34nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 35nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2022-02-17modified 2026-06-17

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+25188 more

references (23)

External citations — patches, advisories, analysis.

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