Issues Fixed in Cloudera Data Science Workbench 1.4.3

TSB-349: SQL Injection Vulnerability in Cloudera Data Science Workbench

An SQL injection vulnerability was found in Cloudera Data Science Workbench. This would allow any authenticated user to run arbitrary queries against CDSW’s internal database. The database contains user contact information, bcrypt-hashed CDSW passwords (in the case of local authentication), API keys, and stored Kerberos keytabs.

Products affected: Cloudera Data Science Workbench (CDSW)

Releases affected: CDSW 1.4.0, 1.4.1, 1.4.2

Users affected: All

Date/time of detection: 2018-10-18

Detected by: Anna Szabo-Simon (Cloudera)

Severity (Low/Medium/High): Critical (9.9): CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Impact: An authenticated CDSW user can arbitrarily access and modify the CDSW internal database. This allows privilege escalation in CDSW, Kubernetes, and the Linux host; creation, deletion, modification, and exfiltration of data, code, and credentials; denial of service; and data loss.

CVE: CVE-2018-20091

Immediate action required:

1. Strongly consider performing a backup before beginning. We advise you to have a backup before performing any upgrade and before beginning this remediation work.

2. Upgrade to Cloudera Data Science Workbench 1.4.3 (or higher).

3. In an abundance of caution Cloudera recommends that you revoke credentials and secrets stored by CDSW. To revoke these credentials:

   1. Change the password for any account with a keytab or kerberos credential that has been stored in CDSW. This includes the Kerberos principals for the associated CDH cluster if entered on the CDSW “Hadoop Authentication” user settings page.

   2. With Cloudera Data Science Workbench 1.4.3 running, run the following remediation script on each CDSW host, including the master and all workers: Remediation Script for TSB-349

      Note: Cloudera Data Science Workbench will become unavailable during this time.

   3. The script performs the following actions:

      1. If using local user authentication, logs out every user and resets their CDSW password.

      2. Regenerates or deletes various keys for every user.

      3. Resets secrets used for internal communications.

   4. Fully stop and start Cloudera Data Science Workbench (a restart is not sufficient).

      • For CSD-based deployments, restart the CDSW service in Cloudera Manager.

        OR

      • For RPM-based deployments, run cdsw stop followed by cdsw start on the CDSW master host.

   5. If using internal TLS termination: revoke and regenerate the CDSW TLS certificate and key.

   6. For each user, revoke the previous CDSW-generated SSH public key for git integration on the git side (the private key in CDSW has already been deleted). A new SSH key pair has already been generated and should be installed in the old key’s place.

   7. Revoke and regenerate any credential stored within a CDSW project, including any passwords stored in projects’ environment variables.

4. Verify all CDSW settings to ensure they are unchanged (e.g. SMTP server, authentication settings, custom docker images, host mounts, etc).

5. Treat all CDSW hosts as potentially compromised with root access. Remediate per your policy.

Addressed in release/refresh/patch: Cloudera Data Science Workbench 1.4.3

For the latest update on this issue see the corresponding Knowledge article:

TSB 2019-349: CDSW SQL Injection Vulnerability

TSB-350: Risk of Data Loss During Cloudera Data Science Workbench (CDSW) Shutdown and Restart

Stopping Cloudera Data Science Workbench involves unmounting the NFS volumes that store CDSW project directories and then cleaning up a folder where CDSW stores its temporary state. However, due to a race condition, this NFS unmount process can take too long or fail altogether. If this happens, any CDSW projects that remain mounted will be deleted.

TSB-2018-346 was released in the time-frame of CDSW 1.4.2 to fix this issue, but it only turned out to be a partial fix. With CDSW 1.4.3, we have fixed the issue permanently. However, the script that was provided with TSB-2018-346 still ensures that data loss is prevented and must be used to shutdown/restart all the affected CDSW released listed below. The same script is also available under the Immediate Action Required section below.

Products affected: Cloudera Data Science Workbench

Users affected: This potentially affects all CDSW users.

Detected by: Nehmé Tohmé (Cloudera)

Severity (Low/Medium/High): High

Impact: Potential data loss.

CVE: N/A

Immediate action required: If you are running any of the affected Cloudera Data Science Workbench versions, you must run the following script on the CDSW master host every time before you stop or restart Cloudera Data Science Workbench. Failure to do so can result in data loss.

This script should also be run before initiating a Cloudera Data Science Workbench upgrade. As always, we recommend creating a full backup prior to beginning an upgrade.

cdsw_protect_stop_restart.sh - Available for download at: cdsw_protect_stop_restart.sh.

#!/bin/bash

set -e

cat << EXPLANATION


This script is a workaround for Cloudera TSB-346 and TSB-350. It protects your
CDSW projects from a rare race condition that can result in data loss.
Run this script before stopping the CDSW service, irrespective of whether
the stop precedes a restart, upgrade, or any other task.

Run this script only on the master node of your CDSW cluster.

You will be asked to specify a target folder on the master node where the
script will save a backup of all your project files. Make sure the target
folder has enough free space to accommodate all of your project files. To
determine how much space is required, run 'du -hs /var/lib/cdsw/current/projects'
on the CDSW master node.

This script will first back up your project files to the specified target
folder. It will then temporarily move your project files aside to protect
against the data loss condition. At that point, it is safe to stop the CDSW
service. After CDSW has stopped, the script will move the project files back
into place.

Note: This workaround is not required for CDSW 1.4.3 and higher.



EXPLANATION

read -p "Enter target folder for backups: " backup_target

echo "Backing up to $backup_target..."
rsync -azp /var/lib/cdsw/current/projects "$backup_target"

read -n 1 -p "Backup complete. Press enter when you are ready to stop CDSW: "

echo "Deleting all Kubernetes resources..."
kubectl delete configmaps,deployments,daemonsets,replicasets,services,ingress,secrets,persistentvolumes,persistentvolumeclaims,jobs --all
kubectl delete pods --all

echo "Temporarily saving project files to /var/lib/cdsw/current/projects_tmp..."
mkdir /var/lib/cdsw/current/projects_tmp
mv /var/lib/cdsw/current/projects/* /var/lib/cdsw/current/projects_tmp

echo -e "Please stop the CDSW service."

read -n 1 -p "Press enter when CDSW has stopped: "

echo "Moving projects back into place..."
mv /var/lib/cdsw/current/projects_tmp/* /var/lib/cdsw/current/projects
rm -rf /var/lib/cdsw/current/projects_tmp

echo -e "Done. You may now upgrade or start the CDSW service."
echo -e "When CDSW is running, if desired, you may delete the backup data at $backup_target"

Addressed in release/refresh/patch: This issue is fixed in Cloudera Data Science Workbench 1.4.3.

Note that you are required to run the workaround script above when you upgrade from an affected version to a release with the fix. This helps guard against data loss when the affected version needs to be shut down during the upgrade process.

TSB-351: Unauthorized Project Access in Cloudera Data Science Workbench

Malicious CDSW users can bypass project permission checks and gain read-write access to any project folder in CDSW.

Products affected: Cloudera Data Science Workbench

Releases affected: Cloudera Data Science Workbench 1.4.0, 1.4.1, 1.4.2

Users affected: All CDSW Users

Date/time of detection: 10/29/2018

Detected by: Che-Yuan Liang (Cloudera)

Severity (Low/Medium/High): High (8.3: CVSS :3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L)

Impact: Project data can be read or written (changed, destroyed) by any Cloudera Data Science Workbench user.

CVE: CVE-2018-20090

Immediate action required:

Upgrade to a version of Cloudera Data Science Workbench with the fix (version 1.4.3, 1.5.0, or higher).

Addressed in release/refresh/patch: Cloudera Data Science Workbench 1.4.3 (and higher)

For the latest update on this issue see the corresponding Knowledge article:

TSB 2019-351: Unauthorized Project Access in Cloudera Data Science Workbench

Other Notable Fixed Issues in Cloudera Data Science Workbench 1.4.3