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Security Bulletin: Multiple Security Vulnerabilities affect IBM Cloud Private Kubernetes

Security Bulletin


Summary

Multiple Security Vulnerabilities affect IBM Cloud Private Kubernetes

Vulnerability Details

CVEID: CVE-2019-4119
DESCRIPTION: IBM Cloud Private Kubernetes API server can be used as an HTTP proxy to not only cluster internal but also external target IP addresses.
CVSS Base Score: 3.1
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/158145 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N)

CVEID: CVE-2019-9946
DESCRIPTION: Kubernetes could provide weaker than expected security, caused by an interaction when paired with the embedded CNI (Container Networking Interface) that uses the portmap plugin. The portmap plugin inserts rules at the front of the iptables nat chains which would take precedence over the KUBE- SERVICES chain. The HostPort/portmap rule allows for matching of incoming traffic even if there are better fitting.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/158803 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID: CVE-2019-1002100
DESCRIPTION: The Kubernetes API server is vulnerable to a denial of service. By sending a specially crafted patch of type "json-patch" requests, a remote authenticated attacker could exploit this vulnerability to consume an excessive amount of resources.
CVSS Base Score: 6.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/157685 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

CVEID: CVE-2019-1002101
DESCRIPTION: Kubernetes could allow a remote attacker to traverse directories on the system, caused by the improper handling of symlinks. By persuading a victim to use the kubectl cp command or the oc cp command with a malicious container, an attacker could replace or delete arbitrary files on the host machine.
CVSS Base Score: 6.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/158804 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N)

CVEID: CVE-2019-11243
DESCRIPTION: Kubernetes could allow a remote attacker to bypass security restrictions, caused by the failure to effectively clear service account credentials loaded using rest.InClusterConfig() by the rest.AnonymousClientConfig() method. By sending a specially-crafted request, an attacker could exploit this vulnerability to send the loaded service account token with requests.
CVSS Base Score: 5.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/160040 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

Affected Products and Versions

IBM Cloud Private 2.1.x, 3.1.0, 3.1.1, 3.1.2

Remediation/Fixes

Product defect fixes and security updates are only available for the two most recent Continuous Delivery (CD) update packages

  • IBM Cloud Private 3.1.2
  • IBM Cloud Private 3.1.1 
 
For IBM Cloud Private 3.1.2, apply patch:

For IBM Cloud Private 3.1.1, apply patch:

For IBM Cloud Private, 2.1.x, 3.1.0:
  • Upgrade to the latest Continuous Delivery (CD) update package, IBM Cloud Private 3.2. 
  • If required, individual product fixes can be made available between CD update packages for resolution of problems. Contact IBM support for assistance

Workarounds and Mitigations

None

Get Notified about Future Security Bulletins

Reference

Complete CVSS v3 Guide
On-line Calculator v3

Related Information

IBM Secure Engineering Web Portal
IBM Product Security Incident Response Blog

Change History

15 May 2019 - Original version published

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.

Disclaimer

According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.

Document information

More support for: IBM Cloud Private

Software version: All Versions

Operating system(s): Linux

Reference #: 0878460

Modified date: 15 May 2019