Velociraptor: Low-priv analyst reads arbitrary server files via ungated sql() VQL plugin

Velociraptor is a tool for collecting host-based state information using Velociraptor Query Language (VQL) queries. Prior to 0.77.2, SQLPlugin.Call in vql/parsers/sql/sql.go does not enforce plugin-level FILESYSTEM_READ or NETWORK checks before the mysql and postgres branches pass a caller-controlled connstring to sql.Open, allowing arbitrary outbound database connections. With attacker-controlled MySQL connection options that enable local-infile access, a rogue MySQL server can request files readable by the Velociraptor server process, including root-readable files when that process runs as root. The SQLite file accessor still enforces FILESYSTEM_READ, but a low-privilege analyst with ANY_QUERY can use the zero-permission data accessor and ATTACH DATABASE to create files without the plugin-level check. This issue is fixed in version 0.77.2.