Name: CVE-2021-3493: Privilege Context Switching Error
Creator: Rapid7
Published: 2021-04-17T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-3493, CWE-863, CWE-270, CWE-862, Exploited in the Wild, CISA KEV Exploit, Metasploit Module, CVSS 8.8, EPSS 0.49166, CISA KEV

The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.

CVSS Details

CVSS 3.1 Base Score: 8.8
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	Upgrade linux	Jul 30, 2024	Apr 17, 2021
Ubuntu	—	Upgrade linux-image-5.8.0-50-lowlatencyUpgrade linux-image-virtual-hwe-18.04Upgrade linux-image-azureUpgrade linux-image-dell300xUpgrade linux-image-oracle-lts-18.04Upgrade linux-image-generic-hwe-20.04Upgrade linux-image-lowlatency-hwe-16.04Upgrade linux-image-5.8.0-50-generic-64kUpgrade linux-image-gkeUpgrade linux-image-aws-lts-18.04Upgrade linux-image-4.4.0-1127-awsUpgrade linux-image-powerpc64-smpUpgrade linux-image-powerpc64-emb-lts-xenialUpgrade linux-image-raspiUpgrade linux-image-aws-hweUpgrade linux-image-5.8.0-1026-oracleUpgrade linux-image-powerpc-smp-lts-xenialUpgrade linux-image-kvmUpgrade linux-image-5.4.0-1014-gkeopUpgrade linux-image-4.15.0-1099-awsUpgrade linux-image-raspi-hwe-18.04Upgrade linux-image-5.4.0-1038-kvmUpgrade linux-image-4.4.0-1091-awsUpgrade linux-image-azure-lts-18.04Upgrade linux-image-5.8.0-50-generic-lpaeUpgrade linux-image-gke-5.3Upgrade linux-image-4.4.0-209-powerpc-smpUpgrade linux-image-4.15.0-142-genericUpgrade linux-image-lowlatency-hwe-18.04Upgrade linux-image-5.4.0-72-generic-lpaeUpgrade linux-image-snapdragonUpgrade linux-image-generic-lpae-hwe-20.04Upgrade linux-image-5.4.0-1046-azureUpgrade linux-image-5.8.0-1029-azureUpgrade linux-image-5.3.0-73-genericUpgrade linux-image-5.4.0-1042-gcpUpgrade linux-image-powerpc-e500mc-lts-xenialUpgrade linux-image-4.15.0-1084-raspi2Upgrade linux-image-4.4.0-209-genericUpgrade linux-image-awsUpgrade linux-image-5.4.0-1045-awsUpgrade linux-image-generic-hwe-18.04Upgrade linux-image-gcpUpgrade linux-image-oem-osp1Upgrade linux-image-generic-lpae-hwe-16.04Upgrade linux-image-4.4.0-1151-raspi2Upgrade linux-image-4.4.0-209-powerpc64-smpUpgrade linux-image-virtual-hwe-20.04Upgrade linux-image-5.8.0-1021-raspiUpgrade linux-image-5.8.0-1021-raspi-nolpaeUpgrade linux-image-gkeop-5.3Upgrade linux-image-5.8.0-50-genericUpgrade linux-image-lowlatency-lts-xenialUpgrade linux-image-oem-20.04Upgrade linux-image-4.4.0-209-powerpc64-embUpgrade linux-image-virtual-lts-xenialUpgrade linux-image-gke-5.4Upgrade linux-image-5.6.0-1054-oemUpgrade linux-image-powerpc64-embUpgrade linux-image-generic-lpaeUpgrade linux-image-5.3.0-1039-raspi2Upgrade linux-image-generic-lpae-lts-xenialUpgrade linux-image-virtual-hwe-16.04Upgrade linux-image-gkeopUpgrade linux-image-generic-64k-hwe-20.04Upgrade linux-image-gcp-lts-18.04Upgrade linux-image-powerpc-smpUpgrade linux-image-generic-lts-xenialUpgrade linux-image-raspi-nolpaeUpgrade linux-image-5.4.0-1034-raspiUpgrade linux-image-4.4.0-209-generic-lpaeUpgrade linux-image-generic-lpae-hwe-18.04Upgrade linux-image-5.3.0-1042-gkeUpgrade linux-image-oracleUpgrade linux-image-lowlatencyUpgrade linux-image-5.4.0-1043-oracleUpgrade linux-image-4.4.0-209-powerpc-e500mcUpgrade linux-image-4.4.0-1092-kvmUpgrade linux-image-4.15.0-142-lowlatencyUpgrade linux-image-lowlatency-hwe-20.04Upgrade linux-image-oem-20.04bUpgrade linux-image-5.4.0-72-lowlatencyUpgrade linux-image-gkeop-5.4Upgrade linux-image-generic-64kUpgrade linux-image-snapdragon-hwe-18.04Upgrade linux-image-virtualUpgrade linux-image-4.15.0-1101-snapdragonUpgrade linux-image-5.8.0-1030-awsUpgrade linux-image-4.15.0-1098-gcpUpgrade linux-image-4.15.0-1090-kvmUpgrade linux-image-4.4.0-1155-snapdragonUpgrade linux-image-raspi2Upgrade linux-image-oemUpgrade linux-image-4.15.0-1017-dell300xUpgrade linux-image-5.8.0-1024-kvmUpgrade linux-image-4.15.0-1070-oracleUpgrade linux-image-4.15.0-142-generic-lpaeUpgrade linux-image-5.10.0-1022-oemUpgrade linux-image-powerpc64-smp-lts-xenialUpgrade linux-image-5.8.0-1028-gcpUpgrade linux-image-5.3.0-73-lowlatencyUpgrade linux-image-4.4.0-209-lowlatencyUpgrade linux-image-5.4.0-72-genericUpgrade linux-image-genericUpgrade linux-image-generic-hwe-16.04Upgrade linux-image-raspi2-hwe-18.04Upgrade linux-image-5.4.0-1042-gkeUpgrade linux-image-powerpc-e500mc	Apr 16, 2021	Apr 15, 2021

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CVSS Details

Covered by Rapid7

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