CVE-2016-6653 MySQL Audit logs sent to Syslog


Severity

High

Vendor

Cloud Foundry Foundation

Versions Affected
  • Cloud Foundry MySQL Release versions 27[1] and 28[2]
Description

MariaDB’s audit_plugin, incorporated in cf-mysql-release starting with cf-mysql-release v27, allows the Operator to enable audit trails, which log all queries sent to the SQL server. With the incorporation of this plugin, a bug was introduced that causes those logs to be sent to syslog. Depending on the nature of the applications that use cf-mysql, these audit logs may contain Personally Identifiable Information (PII) of application users, including unencrypted application access credentials and any application-specific data written to the database.

The audit_plugin automatically redacts credentials in MySQL user creation. MySQL server access credentials are not sent to syslog.

Note: The property, cf_mysql.mysql.server_audit_events, which enables Audit logging is not enabled by default in the release’s spec file. The audit feature must have been manually enabled by an Operator before deploying.

Mitigation

OSS users are strongly encouraged to follow one of the mitigations below:

  • Disable audit logging by deleting the values of cf_mysql.mysql.server_audit_events and re-deploying.
  • Deploy cf-mysql-release v29 when available.
  • Decide how to best handle audit log records that have been stored by your syslog server (implementation varies).
Examples

Below are several examples of audit log events as they will appear in syslog. Scan for entries like these in order to validate that you are no longer sending audit logs to syslog.

20160926
19:55:49,9da585c7-1abc-1234-a6b2-7ee157f6ba65,root,192.0.2.11,118512,16585118,QUERY,mysql_broker,'CREATE USER 'zconN9KAQ6PwXsQC' IDENTIFIED BY *****',0

20160926
22:33:02,d27a463f-x123-1234-96f4-d0ce7b6b298e,EN0wrPpthGzaC7pU,192.0.2.11,120867,29195687,QUERY,cf_fa403c9e_1234_1234_ad0a_70d53d277dbc,'SELECT `partition_spec`.* FROM `partition_spec` WHERE `partition_spec`.`name` = 'ordered' LIMIT 1',0

20160926
22:33:02,d27a463f-x123-1234-96f4-d0ce7b6b298e,dX3qqBoWRGJGZoPx,192.0.2.11,444,29195516,QUERY,cf_da07adfc_123x_1234_a934_dae104226a95,'SELECT `daemon`.* FROM `daemon` WHERE `daemon`.`name` = 'ordered_delayed_job_workers' LIMIT 1',0

Credit

This issue was discovered by the Cloud Foundry cf-mysql development team.

References
History

2016-09-29: Initial vulnerability report published