CVE-2026-22444

/// Technical description

The "create core" API of Apache Solr 8.6 through 9.10.0 lacks sufficient input validation on some API parameters, which can cause Solr to check the existence of and attempt to read file-system paths that should be disallowed by Solr's "allowPaths" security setting https://https://solr.apache.org/guide/solr/latest/configuration-guide/configuring-solr-xml.html#the-solr-element .  These read-only accesses can allow users to create cores using unexpected configsets if any are accessible via the filesystem.  On Windows systems configured to allow UNC paths this can additionally cause disclosure of NTLM "user" hashes. 

Solr deployments are subject to this vulnerability if they meet the following criteria:

* Solr is running in its "standalone" mode.

* Solr's "allowPath" setting is being used to restrict file access to certain directories.

* Solr's "create core" API is exposed and accessible to untrusted users.  This can happen if Solr's RuleBasedAuthorizationPlugin https://solr.ap

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References