CVE-2019-1002101 - Link Following vulnerability in Kubernetes and Redhat products

Publication

2019-04-01

Last modification

2019-04-09

Summary

The kubectl cp command allows copying files between containers and the user machine. To copy files from a container, Kubernetes creates a tar inside the container, copies it over the network, and kubectl unpacks it on the user?s machine. If the tar binary in the container is malicious, it could run any code and output unexpected, malicious results. An attacker could use this to write files to any path on the user?s machine when kubectl cp is called, limited only by the system permissions of the local user. The untar function can both create and follow symbolic links. The issue is resolved in kubectl v1.11.9, v1.12.7, v1.13.5, and v1.14.0.

Description

Kubernetes is prone to a vulnerability that may allow attackers to overwrite arbitrary files. Successful exploits may allow an attacker to write arbitrary files in the context of the user running the affected application. Versions prior to kubernetes 1.11.9, 1.12.7, 1.13.5, and 1.14.0 are vulnerable.

Solution

Updates are available. Please see the references or vendor advisory for more information.

Exploit

Currently, we are not aware of any working exploits.

Classification

CWE-59 - Link Following

Risk level (CVSS AV:N/AC:M/Au:N/C:N/I:P/A:P)

Medium

5.8

Access Vector

  • Network
  • Adjacent Network
  • Local

Access Complexity

  • Low
  • Medium
  • High

Authentication

  • None
  • Single
  • Multiple

Confident. Impact

  • Complete
  • Partial
  • None

Integrity Impact

  • Complete
  • Partial
  • None