CVE-2020-1716: Ceph-ansible Auth Bypass Vulnerability

CVE-2020-1716 Overview

A critical hardcoded credentials vulnerability was discovered in the ceph-ansible playbook that could allow authenticated attackers to compromise Ceph storage clusters. The playbook contained hardcoded passwords being used as default credentials during Ceph service deployments, creating a significant security risk for organizations relying on this automation tool for their distributed storage infrastructure.

Critical Impact

Any authenticated attacker can exploit these hardcoded default passwords to brute-force Ceph deployments and gain full administrator access to Ceph clusters via the Ceph dashboard, enabling unauthorized read, write, and delete operations as well as configuration modifications.

Affected Products

• ceph-ansible versions prior to 6.0.0alpha1
• Ceph storage cluster deployments using affected ceph-ansible playbooks
• Systems with Ceph dashboard enabled using default hardcoded credentials

Discovery Timeline

• 2021-05-28 - CVE-2020-1716 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2020-1716

Vulnerability Analysis

This vulnerability stems from CWE-798 (Use of Hard-coded Credentials), a configuration and design flaw that introduces predictable authentication bypass opportunities. The ceph-ansible playbook, designed to automate Ceph storage cluster deployments, embedded static passwords directly in its configuration. These hardcoded values were then applied as default credentials across all deployments that did not explicitly override them.

The impact is particularly severe because Ceph is a distributed storage platform often used in enterprise and cloud environments to manage large-scale object, block, and file storage. Compromising the Ceph dashboard grants attackers the ability to manipulate cluster configurations, access stored data, and potentially disrupt storage services affecting dependent applications and infrastructure.

Root Cause

The root cause of this vulnerability lies in the ceph-ansible playbook's design decision to include hardcoded passwords for convenience during automated deployments. This approach prioritized ease of initial setup over security, creating a scenario where deployments that failed to customize these credentials would inherit the publicly known default passwords. The lack of mandatory password customization during the deployment process compounded this issue.

Attack Vector

The attack vector for CVE-2020-1716 is network-based, requiring only low-privilege authenticated access to initiate. An attacker who has obtained or guessed the hardcoded default credentials can authenticate to the Ceph dashboard remotely. Once authenticated with administrator privileges, the attacker gains comprehensive control over the storage cluster.

The exploitation flow involves identifying Ceph deployments using affected ceph-ansible versions, attempting authentication with the known default credentials, and upon successful login, leveraging administrator access to perform malicious operations including data exfiltration, modification, or deletion.

Detection Methods for CVE-2020-1716

Indicators of Compromise

• Unexpected or unauthorized login attempts to the Ceph dashboard from unknown IP addresses
• Successful authentication events using default or known hardcoded credentials
• Unusual administrative actions in Ceph cluster logs such as configuration changes or data operations
• New or modified user accounts in the Ceph authentication system

Detection Strategies

• Review ceph-ansible playbook configurations to identify the presence of default or hardcoded passwords
• Audit Ceph dashboard access logs for authentication patterns indicating credential brute-forcing
• Implement alerting for administrative actions performed outside normal operational windows
• Cross-reference user accounts against authorized personnel lists to identify rogue accounts

Monitoring Recommendations

• Enable comprehensive logging for Ceph dashboard authentication and administrative operations
• Deploy network monitoring to detect unusual traffic patterns to Ceph management interfaces
• Implement SIEM correlation rules to identify rapid successive login attempts indicative of brute-forcing
• Establish baseline behavioral profiles for Ceph cluster administrators to detect anomalous activity

How to Mitigate CVE-2020-1716

Immediate Actions Required

• Upgrade ceph-ansible to version 6.0.0alpha1 or later immediately
• Change all default and hardcoded credentials on existing Ceph deployments to strong, unique passwords
• Restrict network access to Ceph dashboard interfaces using firewalls and access control lists
• Conduct an audit of all Ceph cluster user accounts to identify and remove unauthorized entries

Patch Information

The vulnerability is addressed in ceph-ansible version 6.0.0alpha1 and later releases. Organizations should upgrade to the latest stable version of ceph-ansible to ensure they receive this fix along with other security improvements. For detailed information about the vulnerability and remediation guidance, refer to the Red Hat Bug Report #1795592.

Workarounds

• Manually override all default passwords in ceph-ansible playbook configurations before deployment
• Implement network segmentation to isolate Ceph management interfaces from untrusted networks
• Enable multi-factor authentication for Ceph dashboard access where supported
• Deploy intrusion detection systems to monitor for unauthorized access attempts to Ceph services

# Configuration example: Override default credentials in ceph-ansible
# Edit group_vars/all.yml to set custom passwords before deployment
ceph_dashboard_admin_password: "<strong-unique-password>"
grafana_admin_password: "<strong-unique-password>"