In Couchbase Sync Gateway 2.1.2, an attacker with access to the Sync Gateway’s public REST API was able to issue additional N1QL statements and extract sensitive data or call arbitrary N1QL functions through the parameters "startkey" and "endkey" on the "_all_docs" endpoint. By issuing nested queries with CPU-intensive operations they may have been able to cause increased resource usage and denial of service conditions. The _all_docs endpoint is not required for Couchbase Mobile replication and external access to this REST endpoint has been blocked to mitigate this issue. This issue has been fixed in versions 2.5.0 and 2.1.3.
The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.
| Link | Tags |
|---|---|
| https://docs.couchbase.com/sync-gateway/2.5/release-notes.html | release notes vendor advisory |
| https://research.hisolutions.com/2019/06/n1ql-injection-in-couchbase-sync-gateway-cve-2019-9039/ | third party advisory exploit |
| https://www.couchbase.com/resources/security#SecurityAlerts |