High severity · published Feb 17, 2022
CVE-2021-4120
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…
7.8
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FE
Fedora · Fedoraproject
34; 35 · source: NVD
SN
Snapd · Canonical
through 2.54.2 · source: NVD
UL
Ubuntu Linux · Canonical
18.04; 20.04; 21.10 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-4120
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-4120
Exploit
http://www.openwall.com/lists/oss-security/2022/02/18/2
Exploit
https://bugs.launchpad.net/snapd/+bug/1949368
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3QTBN7LLZISXIA4KU4UKDR27Q5PXDS2U/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XCGHG6LJAVJJ72TMART6A7N4Z6MSTGI7/
Patch
https://ubuntu.com/security/notices/USN-5292-1
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