Arch Linux Security Advisory ASA-201711-24 ========================================== Severity: High Date : 2017-11-16 CVE-ID : CVE-2017-12635 CVE-2017-12636 Package : couchdb Type : multiple issues Remote : Yes Link : https://security.archlinux.org/AVG-495 Summary ======= The package couchdb before version 2.1.1-1 is vulnerable to multiple issues including privilege escalation and arbitrary command execution. Resolution ========== Upgrade to 2.1.1-1. # pacman -Syu "couchdb>=2.1.1-1" The problems have been fixed upstream in version 2.1.1. Workaround ========== None. Description =========== - CVE-2017-12635 (privilege escalation) Due to differences in the Erlang-based JSON parser and JavaScript-based JSON parser, it is possible in Apache CouchDB before 1.7.0 and 2.x before 2.1.1 to submit _users documents with duplicate keys for 'roles' used for access control within the database, including the special case '_admin' role, that denotes administrative users. In combination with CVE-2017-12636 (remote command execution), this can be used to give non-admin users access to arbitrary shell commands on the server as the database system user. The JSON parser differences result in behaviour that if two 'roles' keys are available in the JSON, the second one will be used for authorising the document write, but the first 'roles' key is used for subsequent authorization for the newly created user. By design, users can not assign themselves roles. The vulnerability allows non-admin users to give themselves admin privileges. - CVE-2017-12636 (arbitrary command execution) CouchDB administrative users can configure the database server via HTTP(S). Some of the configuration options include paths for operating system-level binaries that are subsequently launched by CouchDB. This allows an admin user in Apache CouchDB before 1.7.0 and 2.x before 2.1.1 to execute arbitrary shell commands as the CouchDB user, including downloading and executing scripts from the public internet. Impact ====== A remote authenticated non-admin user is able to escalate privileges and execute arbitrary commands on the affected host. References ========== https://lists.apache.org/thread.html/6c405bf3f8358e6314076be9f48c89a2e0ddf00... https://justi.cz/security/2017/11/14/couchdb-rce-npm.html https://github.com/apache/couchdb/commit/e01f3009b59a00d81dd1f6d4e807afab08b... https://github.com/apache/couchdb/commit/da27d4dcc7a98c76486f97c356f1c0f4a61... https://security.archlinux.org/CVE-2017-12635 https://security.archlinux.org/CVE-2017-12636