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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.44% probability · 37th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- canonical/snapd · canonical/ubuntu linux · fedoraproject/fedora
- Source
- security@ubuntu.com
References
- http://www.openwall.com/lists/oss-security/2022/02/18/2Exploit, Mailing List, Third Party Advisory
- https://bugs.launchpad.net/snapd/+bug/1949368Exploit, Issue Tracking, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3QTBN7LLZISXIA4KU4UKDR27Q5PXDS2U/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XCGHG6LJAVJJ72TMART6A7N4Z6MSTGI7/
- https://ubuntu.com/security/notices/USN-5292-1Patch, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2022/02/18/2Exploit, Mailing List, Third Party Advisory
- https://bugs.launchpad.net/snapd/+bug/1949368Exploit, Issue Tracking, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3QTBN7LLZISXIA4KU4UKDR27Q5PXDS2U/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XCGHG6LJAVJJ72TMART6A7N4Z6MSTGI7/
- https://ubuntu.com/security/notices/USN-5292-1Patch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.