CVE-2018-1085

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Last Modified: UTC

Important Important Impact What does this mean?
9 CVSS v3 Base Score

Description

OpenShift and Atomic Enterprise Ansible deploys a misconfigured etcd file that causes the SSL client certificate authentication to be disabled. Quotations around the values of ETCD_CLIENT_CERT_AUTH and ETCD_PEER_CLIENT_CERT_AUTH in etcd.conf result in etcd being configured to allow remote users to connect without any authentication if they can access the etcd server bound to the network on the master nodes. An attacker could use this flaw to read and modify all the data about the Openshift cluster in the etcd datastore, potentially adding another compute node, or bringing down the entire cluster.

Statement

This issue affects Openshift Container Platform (OCP) only if you use the container installation method. The container installation method is tech preview in 3.7.1. This issue affected all users who did a containerized etcd in OCP versions 3.7.1-3.6.

If etcd is installed via RPM and run via '/usr/bin/etcd' it's not affected by this flaw. You can check if etcd is being run from '/usr//bin/etcd' using a 'ps' command such as this on the master nodes. If Installed via RPM you should get output similar to:

ps -ef | grep etcd $/usr/bin/etcd --name=master-0.example.com --data-dir=/var/lib/etcd/ --listen-client-urls=Content from 10.0.1.1 is not included.https://10.0.1.1:2379

If etcd is installed via the container method running 'docker ps' on the master will show a container running the registry.access.redhat.com/rhel7/etcd image, eg:

sudo docker ps --filter name=etcd_container $704effa9b0cc registry.access.redhat.com/rhel7/etcd "/usr/bin/etcd" 56 minutes ago Up 56 minutes etcd_container

Mitigation

On master nodes where etcd has been installed using the container method:

0. Verify you can connect to etcd without providing TLS authentication credentials. On any master node, check the ETCD_LISTEN_CLIENT_URLS in /etc/etcd/etcd.conf, and use one of the client urls to connect without providing a certificate, eg:
   curl -4 curl This content is not included.https://10.0.1.1:2379/version -k

0a. If vulnerable output will show something like this:
   {"etcdserver":"3.2.15","etcdcluster":"3.2.0"}

0b. If not affected the connection will fail with:
    curl: (58) NSS: client certificate not found (nickname not specified)

1. update /etc/etcd/etcd.conf on the master nodes to remove quotes from these fields:
   ETCD_PEER_CLIENT_CERT_AUTH="true"
   ETCD_CLIENT_CERT_AUTH="true"
eg.
   ETCD_PEER_CLIENT_CERT_AUTH=true
   ETCD_CLIENT_CERT_AUTH=true

2. Restart the etcd container service:
   sudo systemctl restart etcd_container

3. Test if client authentication is now required using the steps from 0. above.

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2018-1085

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2018-1085

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
Red Hat OpenShift Container Platform 3.9 atomic-openshift Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 atomic-openshift-descheduler Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 atomic-openshift-dockerregistry Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 atomic-openshift-node-problem-detector Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 atomic-openshift-web-console Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 golang-github-prometheus-node_exporter Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 mysql-apb-role Fixed RHSA-2018:2013
Red Hat OpenShift Container Platform 3.9 openshift-ansible Fixed RHSA-2018:2013
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 9 9.8
Attack Vector Adjacent Network Network
Attack Complexity Low Low
Privileges Required Low None
User Interaction None None
Scope Changed Unchanged
Confidentiality Impact High High
Integrity Impact High High
Availability Impact High High

CVSS v3 Vector

Red Hat CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

NVD CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Acknowledgements

Red Hat would like to thank David Hocky (Comcast) for reporting this issue.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

 For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

 A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

 A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

 A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

 The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

 In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.