The following are known Action Replay Codes for CT Special Forces on Nintendo Game Boy Advance (GBA).
These codes were also known as GameShark Codes and in most cases will work on both devices.

These codes are for the U.S. version of the game.

Master Code – Must Be On
d960cd70
bd92ba55
2f4d327f
0e6a8ca2

Infinite Health
e24b259d
785d4de8

Infinite Lives
82e002c7
625fdb25

Inf Machine Gun Ammo
6bcb4aea
d1322c45

Infinite Rockets
33eca238
e7e2febd

Inf Flamethrower
a1acd4cd
7b1713e3

Infinite Gapples
a1acd4cd
7b1713e3

Infinite Grenades
ee0fbe6c
5a44645e