Search Engine Exposed: Apache Solr Flaws Leak Data & Bypass Auth

According to Daily CyberSecurity, two moderate-severity vulnerabilities in Apache Solr could leak data and allow unauthorized access, prompting administrators to update their deployments urgently. The first flaw, CVE-2026-22444, affects Solr versions 8.6 through 9.10.0 and stems from insufficient input validation in the “create core” API, enabling attempts to read file-system paths that should be blocked by Solr’s allowPaths setting and potentially exposing NTLM hashes on Windows deployments using UNC paths.

The second vulnerability, CVE-2026-22022, affects versions 5.3 through 9.10.0 and may allow an unauthorized bypass of the RuleBasedAuthorizationPlugin if certain configuration conditions are met, requiring multiple roles and specific permission rules to be defined, or the catch-all “all” rule left undefined.

The Apache Software Foundation has released Solr 9.10.1 to address both issues, and mitigations include strict permission configurations and ensuring the all rule is explicitly defined with an administrative role. The article notes these flaws mainly impact standalone Solr instances where the create core API is exposed to untrusted users, often due to disabled authorization plugins or permissive roles.