src/cve/2020-1955.rst

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.. _cve/2020-1955:

===========================================================
CVE-2020-1955: Apache CouchDB Remote Privilege Escalation
===========================================================

:Date: 19.05.2020

:Affected: 3.0.0

:Severity: Medium

:Vendor: The Apache Software Foundation

Description
===========

CouchDB version 3.0.0 shipped with a new configuration setting that
governs access control to the entire database server called
`require_valid_user_except_for_up`. It was meant as an extension to the
long-standing setting `require_valid_user`, which in turn requires that
any and all requests to CouchDB will have to be made with valid
credentials, effectively forbidding any anonymous requests.

The new `require_valid_user_except_for_up` is an off-by-default setting
that was meant to allow requiring valid credentials for all endpoints
except for the `/_up` endpoint.

However, the implementation of this made an error that lead to not
enforcing credentials on any endpoint, when enabled.

CouchDB versions :ref:`3.0.1 <release/3.0.1>` and :ref:`3.1.0
<release/3.1.0>` fix this issue.

Mitigation
==========

Users who have not enabled `require_valid_user_except_for_up` are not
affected.

Users who have it enabled can either disable it again, or upgrade to
CouchDB versions :ref:`3.0.1 <release/3.0.1>` and :ref:`3.1.0
<release/3.1.0>`

Credit
======

This issue was discovered by Stefan Klein.