SQLite has two routes to code execution from injection, both with clear preconditions.

load_extension(path) loads a shared library and calls its entry point, which runs native code. This is the direct route, but it is off by default at two levels: many builds compile with loadable extensions disabled entirely, and even when compiled in, extension loading must be turned on by the embedding application through the C API (sqlite3_enable_load_extension() or sqlite3_db_config()). There is no SQL pragma that enables it, so injection cannot unlock this path itself; it works only where the application has already enabled extension loading. Where it has, a malicious library reached through a writable or attacker-supplied path gives execution:

' ; SELECT load_extension('/tmp/evil')-- 

The entry point (named for the file, for example sqlite3_evil_init) runs when the library loads, so merely loading it executes the attacker's code as the application process.

The second route does not need load_extension at all: it chains the file-write primitive with the web layer. Writing a PHP (or other server-side) payload into the document root with ATTACH DATABASE, as shown on the file-manipulation page, produces a script the web server executes on request, giving command execution through HTTP rather than through SQLite itself. This is often the more practical path, since load_extension is usually disabled, while a writable web root plus stacked execution is a common configuration in the small apps that embed SQLite.

References#

• SQLite Documentation: load_extension, enable_load_extension, run-time loadable extensions
• OWASP Testing Guide: Testing for SQL Injection