CVE Vulnerabilities

CVE-2021-21334

Exposure of Resource to Wrong Sphere

Published: Mar 10, 2021 | Modified: Nov 07, 2023
CVSS 3.x
6.3
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu

In containerd (an industry-standard container runtime) before versions 1.3.10 and 1.4.4, containers launched through containerds CRI implementation (through Kubernetes, crictl, or any other pod/container client that uses the containerd CRI service) that share the same image may receive incorrect environment variables, including values that are defined for other containers. If the affected containers have different security contexts, this may allow sensitive information to be unintentionally shared. If you are not using containerds CRI implementation (through one of the mechanisms described above), you are not vulnerable to this issue. If you are not launching multiple containers or Kubernetes pods from the same image which have different environment variables, you are not vulnerable to this issue. If you are not launching multiple containers or Kubernetes pods from the same image in rapid succession, you have reduced likelihood of being vulnerable to this issue This vulnerability has been fixed in containerd 1.3.10 and containerd 1.4.4. Users should update to these versions.

Weakness

The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

Affected Software

Name Vendor Start Version End Version
Containerd Linuxfoundation 1.4.0 *
Containerd Linuxfoundation * *

Extended Description

Resources such as files and directories may be inadvertently exposed through mechanisms such as insecure permissions, or when a program accidentally operates on the wrong object. For example, a program may intend that private files can only be provided to a specific user. This effectively defines a control sphere that is intended to prevent attackers from accessing these private files. If the file permissions are insecure, then parties other than the user will be able to access those files. A separate control sphere might effectively require that the user can only access the private files, but not any other files on the system. If the program does not ensure that the user is only requesting private files, then the user might be able to access other files on the system. In either case, the end result is that a resource has been exposed to the wrong party.

References