Relative Path Traversal vulnerability in Apache Solr. Solr instances running on Windows are vulnerable to arbitrary filepath write-access, due to a lack of input-sanitation in the "configset upload" API. Commonly known as a "zipslip", maliciously constructed ZIP files can use relative filepaths to write data to unanticipated parts of the filesystem. This issue affects Apache Solr: from 6.6 through 9.7.0. Users are recommended to upgrade to version 9.8.0, which fixes the issue. Users unable to upgrade may also safely prevent the issue by using Solr's "Rule-Based Authentication Plugin" to restrict access to the configset upload API, so that it can only be accessed by a trusted set of administrators/users.
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory.