sqlite3-ruby has Use-After-Free in SQLite Aggregate Function Callbacks

Summary

Using Database#create_aggregate, #create_aggregate_handler, or Database#define_aggregator to define an aggregate function, and then using an open statement calling that function after the database has been explicitly closed will result in an invalid memory read and a segmentation fault.

Mitigation

Upgrade to sqlite3 gem v2.9.5 or later.

As a workaround, avoid using an aggregate function after closing the database.

Severity

The sqlite3-ruby maintainers assess this as Low severity. It is reliably triggered after GC when code is structured in a particular way. There is no known general exploit that could be used as a denial of service attack.