Vulnerability Description
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 Code 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.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Apache | Couchdb | < 1.7.0 |
Related Weaknesses (CWE)
References
- http://www.securityfocus.com/bid/101868Third Party AdvisoryVDB Entry
- https://lists.apache.org/thread.html/6c405bf3f8358e6314076be9f48c89a2e0ddf005399
- https://lists.debian.org/debian-lts-announce/2018/01/msg00026.html
- https://security.gentoo.org/glsa/201711-16Third Party Advisory
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpe
- https://www.exploit-db.com/exploits/44498/
- https://www.exploit-db.com/exploits/45019/
- http://www.securityfocus.com/bid/101868Third Party AdvisoryVDB Entry
- https://lists.apache.org/thread.html/6c405bf3f8358e6314076be9f48c89a2e0ddf005399
- https://lists.debian.org/debian-lts-announce/2018/01/msg00026.html
- https://security.gentoo.org/glsa/201711-16Third Party Advisory
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpe
- https://www.exploit-db.com/exploits/44498/
- https://www.exploit-db.com/exploits/45019/
FAQ
What is CVE-2017-12635?
CVE-2017-12635 is a vulnerability with a CVSS score of 9.8 (CRITICAL). 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 f...
How severe is CVE-2017-12635?
CVE-2017-12635 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2017-12635?
Check the references section above for vendor advisories and patch information. Affected products include: Apache Couchdb.