# node labs/security/python-security-lab/python-security-lab.mjs, 2026-11-06 10:36 UTC
SDS Security Lab · python-security-lab · four common Python mistakes
Python 3.14.7 · 2026-11-06 10:36 UTC · throwaway data, this Mac only

== 1. 再現 REPRODUCE: attack inputs against the unsafe version
   unsafe code: SQL in an f-string, pickle.loads on client bytes, subprocess shell=True, open(base / name)
   REPRODUCED  SQL lookup (rows returned): x' OR '1'='1 -> 3
   REPRODUCED  Load a saved session (code ran on load): pickle bytes from the client -> true
   REPRODUCED  ls on a user file name (extra command ran): hello.txt; touch <tmp>/shell-ran.txt -> true
   REPRODUCED  File download (file reachable): ../secret.env -> true

== 2. 実験 EXPERIMENT: attack and normal inputs, both versions
   test                                         input                                      unsafe     fixed     
   SQL lookup (rows returned) (normal)          a@example.test                             1          1         
   SQL lookup (rows returned) (attack)          x' OR '1'='1                               3          0         
   Load a saved session (code ran on load) (att pickle bytes from the client               true       false     
   ls on a user file name (extra command ran) ( hello.txt; touch <tmp>/shell-ran.txt       true       false     
   File download (file reachable) (normal)      hello.txt                                  true       true      
   File download (file reachable) (attack)      ../secret.env                              true       false     

== 3. 対策 FIX
   + db.execute("... WHERE email = ?", (email,))
   + json.loads instead of pickle for anything a client sends
   + subprocess.run(["ls", path]) with a list, no shell
   + (base / name).resolve().is_relative_to(base)
   BLOCKED     SQL lookup (rows returned): x' OR '1'='1 -> 0
   BLOCKED     Load a saved session (code ran on load): pickle bytes from the client -> false
   BLOCKED     ls on a user file name (extra command ran): hello.txt; touch <tmp>/shell-ran.txt -> false
   BLOCKED     File download (file reachable): ../secret.env -> false

== 4. レポート REPORT
   reproduced on unsafe version : 4/4
   blocked by the fix           : 4/4
   normal inputs unchanged      : 2/2
RESULT: FIX WORKS: every attack input reproduced on the unsafe version and was blocked by the fix; normal inputs unchanged