2.10. CVE-2018-11769: Apache CouchDB Remote Code Execution

2.10.1. Description

CouchDB administrative users can configure the database server via HTTP(S). Due to insufficient validation of administrator-supplied configuration settings via the HTTP API, it is possible for a CouchDB administrator user to escalate their privileges to that of the operating system’s user under which CouchDB runs, by bypassing the blacklist of configuration settings that are not allowed to be modified via the HTTP API.

This privilege escalation effectively allows a CouchDB admin user to gain arbitrary remote code execution, bypassing mitigations for CVE-2017-12636 and CVE-2018-8007.

2.10.2. Mitigation

All users should upgrade to CouchDB 2.2.0.

Upgrades from previous 2.x versions in the same series should be seamless.

Users still on CouchDB 1.x should be advised that the Apache CouchDB team no longer support 1.x.

In-place mitigation (on any 1.x release, or 2.x prior to 2.2.0) is possible by removing the _config route from the default.ini file, as follows:

[httpd_global_handlers]
;_config = {couch_httpd_misc_handlers, handle_config_req}

or by blocking access to the /_config (1.x) or /_node/*/_config routes at a reverse proxy in front of the service.