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 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 v3.0 7.8 HIGH
CVSS v2.0 4.6 MEDIUM

7.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.6^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 3.9 / Impact : 6.4

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://ubuntu.com/security/notices/USN-5292-1	Patch Vendor Advisory
https://bugs.launchpad.net/snapd/+bug/1949368	Exploit Issue Tracking Third Party Advisory
http://www.openwall.com/lists/oss-security/2022/02/18/2	Exploit Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XCGHG6LJAVJJ72TMART6A7N4Z6MSTGI7/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3QTBN7LLZISXIA4KU4UKDR27Q5PXDS2U/	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:canonical:snapd:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:20.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:21.10:::::::*

Configuration 3 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:34:::::::*
	cpe:2.3:o:fedoraproject:fedora:35:::::::*

Information

Published : 2022-02-17 15:15

Updated : 2022-03-01 09:07

NVD link : CVE-2021-4120

Mitre link : CVE-2021-4120

JSON object : View

CWE

CWE-20

Improper Input Validation

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Products Affected

canonical

ubuntu_linux
snapd

fedoraproject

fedora

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