Insecure Default Initialization of Resource vulnerability in Apache Solr.
New ConfigSets that are created via a Restore command, which copy a configSet from the backup and give it a new name, are created without setting the trusted metadata. ConfigSets that do not contain the flag are trusted implicitly if the metadata is missing, therefore this leads to trusted ConfigSets that may not have been created with an Authenticated request. trusted ConfigSets are able to load custom code into classloaders, therefore the flag is supposed to only be set when the request that uploads the ConfigSet is Authenticated & Authorized.
This issue affects Apache Solr: from 6.6.0 before 8.11.4, from 9.0.0 before 9.7.0. This issue does not affect Solr instances that are secured via Authentication/Authorization.
Users are primarily recommended to use Authentication and Authorization when running Solr. However, upgrading to version 9.7.0, or 8.11.4 will mitigate this issue otherwise.
The product initializes or sets a resource with a default that is intended to be changed by the administrator, but the default is not secure.
Developers often choose default values that leave the product as open and easy to use as possible out-of-the-box, under the assumption that the administrator can (or should) change the default value. However, this ease-of-use comes at a cost when the default is insecure and the administrator does not change it.