The following firearms can be seen in the film Salt:
Salt is a 2010 action film starring Angelina Jolie as Evelyn Salt, a CIA agent who after being accused of being a Russian sleeper, goes on the run in order to clear her name.
All screencaps are from the trailers and official clips from Yahoo! Movies and IMDB:
Secret Service agents at the White House are armed with Heckler & Koch MP5K submachine guns. Winter also uses a MP5K in the finale.
Rifles
M4A1 Carbine
There are multiple different loadouts of M4 Carbines seen throughout the film in the hands of U.S Army soldiers, CIA agents and NYPD ESU teams.
Colt Model 933
Several CIA tactical unit members can be seen with Colt Model 933s, distinguished from the aforementioned M4A1s by their shorter barrels.
AK-74M
A guard at the Russian boat base is seen with an AK-74M when Salt arrives with Vassily Orlov (Daniel Olbrychski).
Norinco Type 56
At least one Russian on the boat has a AK-type weapon with an underfolding stock, most likely a Norinco Type 56.
SIG SG 552
Salt fires a SIG SG 552 with a RIS handguard and four mags clamped together in the finale.
Other
X26 Taser
Salt takes a X26 taser from a NYPD officer after being arrested in New York, using it to tase the driver of the vehicle she is in and to flee police custody.
M84 Stun Grenade
A M84 stun grenade is tossed into Salt's apartment by CIA agents while they are searching for her.
M67 hand grenade
Salt is seen dropping what appears to be M67 hand grenades in the trailer.
M7 CS gas grenade
A CIA tactical team member tosses M7 CS gas grenade into a room when Salt escapes from the CIA building.