CVE-2017-7660: Apache Solr

High severity, CVSS 7.5. EPSS: 5.6% chance of exploitation in the next 30 days.

Apache Solr uses a PKI based mechanism to secure inter-node communication when security is enabled. It is possible to create a specially crafted node name that does not exist as part of the cluster and point it to a malicious node. This can trick the nodes in cluster to believe that the malicious node is a member of the cluster. So, if Solr users have enabled BasicAuth authentication mechanism using the BasicAuthPlugin or if the user has implemented a custom Authentication plugin, which does not implement either "HttpClientInterceptorPlugin" or "HttpClientBuilderPlugin", his/her servers are vulnerable to this attack. Users who only use SSL without basic authentication or those who use Kerberos are not affected.

Affected products

• Apache Solr: version 5.3.0 only; version 5.3.1 only; version 5.3.2 only; version 5.4.0 only; version 5.4.1 only; version 5.5.0 only; …

Published 2017-07-07. Last modified 2026-06-17.