Date: 08.08.2018
Affected: Apache CouchDB 1.x and ≤2.1.2
Severity: Low
Vendor: The Apache Software Foundation
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.
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.
