From 41d4ac9da348ca33056e271d71588b2dc3a6d48d Mon Sep 17 00:00:00 2001 From: Jia Junjie <62194633+jiajunjie@users.noreply.github.com> Date: Fri, 9 Dec 2022 04:37:08 +0800 Subject: [PATCH] gh-96250: Improve sqlite3 injection attack example (#99270) Co-authored-by: C.A.M. Gerlach Co-authored-by: Erlend E. Aasland --- Doc/library/sqlite3.rst | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/Doc/library/sqlite3.rst b/Doc/library/sqlite3.rst index 960f2966afe1f2..2b6387cbfb5288 100644 --- a/Doc/library/sqlite3.rst +++ b/Doc/library/sqlite3.rst @@ -1929,12 +1929,16 @@ How to use placeholders to bind values in SQL queries SQL operations usually need to use values from Python variables. However, beware of using Python's string operations to assemble queries, as they -are vulnerable to `SQL injection attacks`_ (see the `xkcd webcomic -`_ for a humorous example of what can go wrong):: - - # Never do this -- insecure! - symbol = 'RHAT' - cur.execute("SELECT * FROM stocks WHERE symbol = '%s'" % symbol) +are vulnerable to `SQL injection attacks`_. For example, an attacker can simply +close the single quote and inject ``OR TRUE`` to select all rows:: + + >>> # Never do this -- insecure! + >>> symbol = input() + ' OR TRUE; -- + >>> sql = "SELECT * FROM stocks WHERE symbol = '%s'" % symbol + >>> print(sql) + SELECT * FROM stocks WHERE symbol = '' OR TRUE; --' + >>> cur.execute(sql) Instead, use the DB-API's parameter substitution. To insert a variable into a query string, use a placeholder in the string, and substitute the actual values