LSN-0076-1: Kernel Live Patch Security Notice

It was discovered that the overlayfs implementation in the Linux kernel did not properly validate the application of file system capabilities with respect to user namespaces. A local attacker could use this to gain elevated privileges.CVE-2021-3493 Piotr Krysiuk discovered that the BPF JIT compil...

CVE-2021-3493

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...

Microsoft Azure Sphere Linux namespace ptrace unsigned code execution vulnerability

Summary An unsigned code execution vulnerability exists in the Linux namespace ptrace functionality of Microsoft Azure Sphere 21.01. Specially crafted shellcode could allow an adversary to execute unsigned code. An attacker can change the namespace and use ptrace to modify the code of a running...

OESA-2021-1102 docker security update

Docker is an open source project to build, ship and run any application as a lightweight container. Docker containers are both hardware-agnostic and platform-agnostic. This means they can run anywhere, from your laptop to the largest EC2 compute instance and everything in between - and they don't...

The vulnerability of the `--userns-remap` option, a Docker containerization-enabled deployment and application management automation tool, is related to an incorrect path name limitation for the directory. This vulnerability allows attackers to compromise data integrity.

The vulnerability of the --userns-remap option, a tool for automating application deployment and management in Docker containerized environments, is related to an incorrect restriction on the path name to the directory. Exploiting this vulnerability allows a malicious actor to compromise data...

Oracle Linux 7 / 8 : Unbreakable Enterprise kernel-container (ELSA-2021-9086)

The remote Oracle Linux 7 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2021-9086 advisory. - xen-blkback: fix error handling in xenblkbkmap Jan Beulich Orabug: 32492109 CVE-2021-26930 - xen-scsiback: dont 'handle' error by BUG Jan Beulich...

Oracle Linux 7 / 8 : Unbreakable Enterprise kernel (ELSA-2021-9085)

The remote Oracle Linux 7 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2021-9085 advisory. - xen-blkback: fix error handling in xenblkbkmap Jan Beulich Orabug: 32492109 CVE-2021-26930 - xen-scsiback: dont 'handle' error by BUG Jan Beulich...

CVE-2020-16120

Overlayfs did not properly perform permission checking when copying up files in an overlayfs and could be exploited from within a user namespace, if, for example, unprivileged user namespaces were allowed. It was possible to have a file not readable by an unprivileged user to be copied to a...

CVE-2020-16120

Overlayfs did not properly perform permission checking when copying up files in an overlayfs and could be exploited from within a user namespace, if, for example, unprivileged user namespaces were allowed. It was possible to have a file not readable by an unprivileged user to be copied to a...

AZL-6522 CVE-2020-16120 affecting package kernel for versions less than 5.10.78.1-1

Overlayfs did not properly perform permission checking when copying up files in an overlayfs and could be exploited from within a user namespace, if, for example, unprivileged user namespaces were allowed. It was possible to have a file not readable by an unprivileged user to be copied to a...

Design/Logic Flaw

Overlayfs did not properly perform permission checking when copying up files in an overlayfs and could be exploited from within a user namespace, if, for example, unprivileged user namespaces were allowed. It was possible to have a file not readable by an unprivileged user to be copied to a...

CVE-2020-16120 Unprivileged overlay + shiftfs read access

Overlayfs did not properly perform permission checking when copying up files in an overlayfs and could be exploited from within a user namespace, if, for example, unprivileged user namespaces were allowed. It was possible to have a file not readable by an unprivileged user to be copied to a...

CVE-2020-16120

The CVE-2020-16120 issue concerns Overlayfs in the Linux kernel where permission checks during copy-up were inadequate when used inside a user namespace. It was introduced in kernel 4.19 (ovl: stack file ops) and fixed in kernel 5.8 by patches that verify permissions in ovl_path_open(), switch to...

Privilege Escalation

docker is vulnerable to privilege escalation. The --userns-remap option allows the root user in the remapped namespace, who has access to the host filesystem, to modify files under /var/lib/docker/ and write files with extended privileges...

Vulnerabilities fixed in Docker

Vulnerabilities have been fixed in Docker. A local malicious person can, by exploiting the vulnerability with attribute CVE-2021-21284, gain root privileges from the container on the vulnerable system. To exploit this vulnerability, the Docker daemon must be configured with the --userns-remap...

DEBIAN-CVE-2021-21284

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can...

UBUNTU-CVE-2021-21284

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can...

CVE-2020-16120

A flaw was found in the User namespace on an overlay filesystem in the Linux Kernel, Where a file with no access privilege was able to copy the file to a user defined mount point. An attacker with a special user privilege locally may lead to a kernel information leak problem. Mitigation Red Hat...

CVE-2020-16120

Overlayfs did not properly perform permission checking when copying up files in an overlayfs and could be exploited from within a user namespace, if, for example, unprivileged user namespaces were allowed. It was possible to have a file not readable by an unprivileged user to be copied to a...

OPENSUSE-SU-2020:1552-1 Security update for conmon, fuse-overlayfs, libcontainers-common, podman

This update for conmon, fuse-overlayfs, libcontainers-common, podman fixes the following issues: podman was updated to v2.0.6 bsc1175821 - install missing systemd units for the new Rest API bsc1175957 and a few man-pages that where missing before - Drop varlink API related bits in favor of the ne...