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-862, CWE-270, CWE-863, Exploited in the Wild, CISA KEV Exploit, Metasploit Module, CVSS 8.8, EPSS 0.76767, 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-5.4.0-1043-oracleUpgrade linux-image-4.15.0-1070-oracleUpgrade linux-image-4.15.0-1017-dell300xUpgrade linux-image-generic-lpae-hwe-18.04Upgrade linux-image-raspi2Upgrade linux-image-4.4.0-1155-snapdragonUpgrade linux-image-lowlatencyUpgrade linux-image-generic-64k-hwe-20.04Upgrade linux-image-raspi2-hwe-18.04Upgrade linux-image-generic-lts-xenialUpgrade linux-image-virtualUpgrade linux-image-5.10.0-1022-oemUpgrade linux-image-gcp-lts-18.04Upgrade linux-image-5.4.0-72-genericUpgrade linux-image-5.8.0-50-lowlatencyUpgrade linux-image-powerpc64-smp-lts-xenialUpgrade linux-image-5.4.0-1042-gkeUpgrade linux-image-gkeopUpgrade linux-image-powerpc-smpUpgrade linux-image-gkeop-5.4Upgrade linux-image-generic-lpae-lts-xenialUpgrade linux-image-4.15.0-142-lowlatencyUpgrade linux-image-oemUpgrade linux-image-5.3.0-1042-gkeUpgrade linux-image-snapdragon-hwe-18.04Upgrade linux-image-generic-64kUpgrade linux-image-5.8.0-1030-awsUpgrade linux-image-4.15.0-1098-gcpUpgrade linux-image-raspi-nolpaeUpgrade linux-image-4.15.0-1090-kvmUpgrade linux-image-4.4.0-1092-kvmUpgrade linux-image-5.4.0-1034-raspiUpgrade linux-image-4.4.0-209-lowlatencyUpgrade linux-image-4.15.0-1101-snapdragonUpgrade linux-image-virtual-hwe-16.04Upgrade linux-image-generic-lpaeUpgrade linux-image-powerpc-e500mcUpgrade linux-image-5.4.0-72-lowlatencyUpgrade linux-image-generic-hwe-16.04Upgrade linux-image-lowlatency-hwe-20.04Upgrade linux-image-5.3.0-73-lowlatencyUpgrade linux-image-4.15.0-142-generic-lpaeUpgrade linux-image-4.4.0-209-powerpc-e500mcUpgrade linux-image-5.3.0-1039-raspi2Upgrade linux-image-oem-20.04bUpgrade linux-image-powerpc64-embUpgrade linux-image-genericUpgrade linux-image-5.8.0-1028-gcpUpgrade linux-image-oracleUpgrade linux-image-5.8.0-1024-kvmUpgrade linux-image-4.4.0-209-generic-lpaeUpgrade linux-image-5.4.0-1042-gcpUpgrade linux-image-5.6.0-1054-oemUpgrade linux-image-raspi-hwe-18.04Upgrade linux-image-gke-5.4Upgrade linux-image-powerpc64-emb-lts-xenialUpgrade linux-image-5.4.0-1014-gkeopUpgrade linux-image-4.4.0-209-powerpc64-embUpgrade linux-image-5.4.0-1046-azureUpgrade linux-image-kvmUpgrade linux-image-4.4.0-1091-awsUpgrade linux-image-aws-hweUpgrade linux-image-powerpc64-smpUpgrade linux-image-4.4.0-209-powerpc-smpUpgrade linux-image-4.15.0-1084-raspi2Upgrade linux-image-awsUpgrade linux-image-azureUpgrade linux-image-4.15.0-142-genericUpgrade linux-image-lowlatency-hwe-18.04Upgrade linux-image-snapdragonUpgrade linux-image-4.15.0-1113-azureUpgrade linux-image-5.8.0-1021-raspi-nolpaeUpgrade linux-image-5.8.0-50-generic-64kUpgrade linux-image-4.4.0-209-powerpc64-smpUpgrade linux-image-generic-hwe-20.04Upgrade linux-image-dell300xUpgrade linux-image-4.4.0-1127-awsUpgrade linux-image-gcpUpgrade linux-image-generic-lpae-hwe-20.04Upgrade linux-image-aws-lts-18.04Upgrade linux-image-powerpc-e500mc-lts-xenialUpgrade linux-image-oracle-lts-18.04Upgrade linux-image-5.4.0-1045-awsUpgrade linux-image-4.4.0-1151-raspi2Upgrade linux-image-5.8.0-1029-azureUpgrade linux-image-virtual-hwe-20.04Upgrade linux-image-gkeUpgrade linux-image-4.4.0-209-genericUpgrade linux-image-virtual-lts-xenialUpgrade linux-image-oem-20.04Upgrade linux-image-5.8.0-1026-oracleUpgrade linux-image-5.8.0-50-generic-lpaeUpgrade linux-image-lowlatency-hwe-16.04Upgrade linux-image-virtual-hwe-18.04Upgrade linux-image-5.8.0-1021-raspiUpgrade linux-image-gkeop-5.3Upgrade linux-image-4.15.0-1099-awsUpgrade linux-image-5.4.0-72-generic-lpaeUpgrade linux-image-generic-hwe-18.04Upgrade linux-image-gke-5.3Upgrade linux-image-azure-lts-18.04Upgrade linux-image-5.4.0-1038-kvmUpgrade linux-image-5.8.0-50-genericUpgrade linux-image-5.3.0-73-genericUpgrade linux-image-generic-lpae-hwe-16.04Upgrade linux-image-powerpc-smp-lts-xenialUpgrade linux-image-oem-osp1Upgrade linux-image-lowlatency-lts-xenialUpgrade linux-image-raspi	Apr 16, 2021	Apr 15, 2021

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CVSS Details

Covered by Rapid7

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