PDO\Sqlite::loadExtension loads arbitrary shared objects

[thomas-chauchefoin-tob]

Description

Unlike SQLite3::loadExtension, Pdo\Sqlite::loadExtension does not check sqlite3.extension_dir and calls sqlite3_load_extension with the absolute path to the extension parameter. This allows executing native code from PHP code subject to open_basedir / disable_functions (which are not security boundaries anyway).

php-src/ext/pdo_sqlite/pdo_sqlite.c

Lines 102 to 113 in 769441b

	if (!VCWD_REALPATH(extension, fullpath)) {
	zend_throw_exception_ex(php_pdo_get_exception(), 0, "Unable to load extension \"%s\"", extension);
	RETURN_THROWS();
	}
	sqlite3 *sqlite_handle;
	sqlite_handle = db_handle->db;
	/* This only enables extension loading for the C api, not for SQL */
	sqlite3_db_config(sqlite_handle, SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION, 1, NULL);
	if (sqlite3_load_extension(sqlite_handle, fullpath, 0, &errtext) != SQLITE_OK) {

I'll open a PR with my patch later this week. It introduces a similar check to SQLite3::loadExtension and restricts extension loading to a trusted directory (sqlite3.extension_dir) set in advance.

PHP Version

PHP 8.6.0-dev (cli) (built: May 10 2026 23:58:07) (NTS)
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Operating System

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