vulnerability

Ubuntu: (Multiple Advisories) (CVE-2021-3493): Linux kernel (OEM) vulnerabilities

Severity
7
CVSS
(AV:L/AC:L/Au:N/C:C/I:C/A:C)
Published
Apr 15, 2021
Added
Apr 16, 2021
Modified
Mar 27, 2026

Description

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.

Solutions

ubuntu-upgrade-linux-image-4-15-0-1017-dell300xubuntu-upgrade-linux-image-4-15-0-1070-oracleubuntu-upgrade-linux-image-4-15-0-1084-raspi2ubuntu-upgrade-linux-image-4-15-0-1090-kvmubuntu-upgrade-linux-image-4-15-0-1098-gcpubuntu-upgrade-linux-image-4-15-0-1099-awsubuntu-upgrade-linux-image-4-15-0-1101-snapdragonubuntu-upgrade-linux-image-4-15-0-1113-azureubuntu-upgrade-linux-image-4-15-0-142-genericubuntu-upgrade-linux-image-4-15-0-142-generic-lpaeubuntu-upgrade-linux-image-4-15-0-142-lowlatencyubuntu-upgrade-linux-image-4-4-0-1091-awsubuntu-upgrade-linux-image-4-4-0-1092-kvmubuntu-upgrade-linux-image-4-4-0-1127-awsubuntu-upgrade-linux-image-4-4-0-1151-raspi2ubuntu-upgrade-linux-image-4-4-0-1155-snapdragonubuntu-upgrade-linux-image-4-4-0-209-genericubuntu-upgrade-linux-image-4-4-0-209-generic-lpaeubuntu-upgrade-linux-image-4-4-0-209-lowlatencyubuntu-upgrade-linux-image-4-4-0-209-powerpc-e500mcubuntu-upgrade-linux-image-4-4-0-209-powerpc-smpubuntu-upgrade-linux-image-4-4-0-209-powerpc64-embubuntu-upgrade-linux-image-4-4-0-209-powerpc64-smpubuntu-upgrade-linux-image-5-10-0-1022-oemubuntu-upgrade-linux-image-5-3-0-1039-raspi2ubuntu-upgrade-linux-image-5-3-0-1042-gkeubuntu-upgrade-linux-image-5-3-0-73-genericubuntu-upgrade-linux-image-5-3-0-73-lowlatencyubuntu-upgrade-linux-image-5-4-0-1014-gkeopubuntu-upgrade-linux-image-5-4-0-1034-raspiubuntu-upgrade-linux-image-5-4-0-1038-kvmubuntu-upgrade-linux-image-5-4-0-1042-gcpubuntu-upgrade-linux-image-5-4-0-1042-gkeubuntu-upgrade-linux-image-5-4-0-1043-oracleubuntu-upgrade-linux-image-5-4-0-1045-awsubuntu-upgrade-linux-image-5-4-0-1046-azureubuntu-upgrade-linux-image-5-4-0-72-genericubuntu-upgrade-linux-image-5-4-0-72-generic-lpaeubuntu-upgrade-linux-image-5-4-0-72-lowlatencyubuntu-upgrade-linux-image-5-6-0-1054-oemubuntu-upgrade-linux-image-5-8-0-1021-raspiubuntu-upgrade-linux-image-5-8-0-1021-raspi-nolpaeubuntu-upgrade-linux-image-5-8-0-1024-kvmubuntu-upgrade-linux-image-5-8-0-1026-oracleubuntu-upgrade-linux-image-5-8-0-1028-gcpubuntu-upgrade-linux-image-5-8-0-1029-azureubuntu-upgrade-linux-image-5-8-0-1030-awsubuntu-upgrade-linux-image-5-8-0-50-genericubuntu-upgrade-linux-image-5-8-0-50-generic-64kubuntu-upgrade-linux-image-5-8-0-50-generic-lpaeubuntu-upgrade-linux-image-5-8-0-50-lowlatencyubuntu-upgrade-linux-image-awsubuntu-upgrade-linux-image-aws-hweubuntu-upgrade-linux-image-aws-lts-18-04ubuntu-upgrade-linux-image-azureubuntu-upgrade-linux-image-azure-lts-18-04ubuntu-upgrade-linux-image-dell300xubuntu-upgrade-linux-image-gcpubuntu-upgrade-linux-image-gcp-lts-18-04ubuntu-upgrade-linux-image-genericubuntu-upgrade-linux-image-generic-64kubuntu-upgrade-linux-image-generic-64k-hwe-20-04ubuntu-upgrade-linux-image-generic-hwe-16-04ubuntu-upgrade-linux-image-generic-hwe-18-04ubuntu-upgrade-linux-image-generic-hwe-20-04ubuntu-upgrade-linux-image-generic-lpaeubuntu-upgrade-linux-image-generic-lpae-hwe-16-04ubuntu-upgrade-linux-image-generic-lpae-hwe-18-04ubuntu-upgrade-linux-image-generic-lpae-hwe-20-04ubuntu-upgrade-linux-image-generic-lpae-lts-xenialubuntu-upgrade-linux-image-generic-lts-xenialubuntu-upgrade-linux-image-gkeubuntu-upgrade-linux-image-gke-5-3ubuntu-upgrade-linux-image-gke-5-4ubuntu-upgrade-linux-image-gkeopubuntu-upgrade-linux-image-gkeop-5-3ubuntu-upgrade-linux-image-gkeop-5-4ubuntu-upgrade-linux-image-kvmubuntu-upgrade-linux-image-lowlatencyubuntu-upgrade-linux-image-lowlatency-hwe-16-04ubuntu-upgrade-linux-image-lowlatency-hwe-18-04ubuntu-upgrade-linux-image-lowlatency-hwe-20-04ubuntu-upgrade-linux-image-lowlatency-lts-xenialubuntu-upgrade-linux-image-oemubuntu-upgrade-linux-image-oem-20-04ubuntu-upgrade-linux-image-oem-20-04bubuntu-upgrade-linux-image-oem-osp1ubuntu-upgrade-linux-image-oracleubuntu-upgrade-linux-image-oracle-lts-18-04ubuntu-upgrade-linux-image-powerpc-e500mcubuntu-upgrade-linux-image-powerpc-e500mc-lts-xenialubuntu-upgrade-linux-image-powerpc-smpubuntu-upgrade-linux-image-powerpc-smp-lts-xenialubuntu-upgrade-linux-image-powerpc64-embubuntu-upgrade-linux-image-powerpc64-emb-lts-xenialubuntu-upgrade-linux-image-powerpc64-smpubuntu-upgrade-linux-image-powerpc64-smp-lts-xenialubuntu-upgrade-linux-image-raspiubuntu-upgrade-linux-image-raspi-hwe-18-04ubuntu-upgrade-linux-image-raspi-nolpaeubuntu-upgrade-linux-image-raspi2ubuntu-upgrade-linux-image-raspi2-hwe-18-04ubuntu-upgrade-linux-image-snapdragonubuntu-upgrade-linux-image-snapdragon-hwe-18-04ubuntu-upgrade-linux-image-virtualubuntu-upgrade-linux-image-virtual-hwe-16-04ubuntu-upgrade-linux-image-virtual-hwe-18-04ubuntu-upgrade-linux-image-virtual-hwe-20-04ubuntu-upgrade-linux-image-virtual-lts-xenial
Title
Rapid7 Labs

2026 Global Threat Landscape Report

The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.