ClickhouseAuthenticationFailures #

Authentication failures detected, indicating potential security issues or misconfiguration.

alert: ClickhouseAuthenticationFailures
annotations:
  description: |-
    Authentication failures detected, indicating potential security issues or misconfiguration.
      VALUE = {{ $value }}
      LABELS = {{ $labels }}    
  runbook: https://srerun.github.io/prometheus-alerts/runbooks/clickhouse-internal/clickhouseauthenticationfailures/
  summary: ClickHouse Authentication Failures (instance {{ $labels.instance }})
expr: increase(ClickHouseErrorMetric_AUTHENTICATION_FAILED[5m]) > 0
for: 0m
labels:
  severity: info

Meaning #

The ClickhouseAuthenticationFailures alert is triggered when there is an increase in authentication failures to a Clickhouse instance over a 5-minute period. This alert indicates potential security issues or misconfiguration with the Clickhouse authentication mechanism.

Impact #

• Unauthorized access to sensitive data stored in Clickhouse
• Denial of Service (DoS) to legitimate users due to excessive authentication attempts
• Performance degradation of the Clickhouse instance
• Increased risk of security breaches and data compromise

Diagnosis #

To diagnose the root cause of the authentication failures, follow these steps:

1. Check the Clickhouse logs for error messages related to authentication failures.
2. Verify the Clickhouse configuration files for any changes or misconfigurations.
3. Investigate the network traffic to identify any unusual patterns or sources of authentication attempts.
4. Check the Clickhouse user accounts for any suspicious activity or unauthorized access.
5. Review the system logs for any signs of security breaches or unauthorized access.

Mitigation #

To mitigate the ClickhouseAuthenticationFailures alert, follow these steps:

1. Immediately investigate and address any security breaches or unauthorized access.
2. Check and rectify any misconfigurations in the Clickhouse configuration files.
3. Implement additional security measures such as rate limiting, IP blocking, or multi-factor authentication to prevent brute-force attacks.
4. Monitor Clickhouse logs and system logs for any signs of suspicious activity.
5. Consider implementing a Clickhouse alerting mechanism to notify administrators of authentication failures in real-time.
6. Perform a thorough security audit of the Clickhouse instance and related systems to identify and remediate any vulnerabilities.