Apache Solr Backup/Restore API Remote Code Execution –

– Apache Solr versions 6.0.0 through 8.11.2 and versions 9.0.0 up to 9.4.1 are affected by an unrestricted file upload vulnerability which can result in remote code execution in the context of the user running Apache Solr. When Apache Solr creates a Collection, it will use a specific directory as the classpath and load some classes from it. The backup function of the Collection can export malicious class files uploaded by attackers to the directory, allowing Solr to load custom classes and create arbitrary Java code. Execution can further bypass the Java sandbox configured by Solr, ultimately causing arbitrary command execution. – Read More  – Packet Storm