Apache Solr: ConfigSets created during a backup restore command are trusted implicitly (CVE-2024-45217)

The vulnerability (CVE-2024-45217) in Apache Solr arises from insecure default initialization of ConfigSets created via the Restore command. These ConfigSets copy from backups and are assigned new names but lack explicit 'trusted' metadata. If the 'trusted' flag is missing, Solr treats the ConfigSet as trusted implicitly, allowing it to load custom code into classloaders. This behavior should only occur when the ConfigSet is uploaded through authenticated and authorized requests. Affected versions include Solr >=6.6.0 <8.11.4 and >=9.0.0 <9.7.0. Instances secured with authentication and authorization are not affected. The vulnerability is rated high severity and can be mitigated by upgrading to Solr 8.11.4 or 9.7.0 or by enabling authentication and authorization.

The vulnerability allows ConfigSets created during backup restore operations to be implicitly trusted without authentication, potentially enabling unauthorized loading of custom code into Solr's classloaders. This could lead to unauthorized code execution or other security risks if the Solr instance is not secured with authentication and authorization.

Users are strongly recommended to enable authentication and authorization on Solr instances to prevent exploitation of this vulnerability. Additionally, upgrading affected Solr versions to 8.11.4 or 9.7.0 or later will mitigate the issue. No other specific mitigations are indicated. Instances already secured with authentication and authorization are not vulnerable.