Here is the full list of all 27 Call of Duty: Modern Warfare achievements.
Complete all Special Operations missions.
Complete every single player mission on Veteran or Realism difficulty.
Complete 'The Wolf's Den' tunnels using only the 1911.
Burn 4 enemies with a single molotov.
Blow up 3 tripwires with explosives.
Reach Barkov's lab entrance using only drone strikes.
Never get hit by the sniper while escaping captivity.
Kill 3 enemies while you are on a ladder.
Save Alpha 3-2 from being downed.
Kill at least one enemy while inside The Reading Place, Aural Chic, and both Subway undergrounds.
Get at least one kill with eight different weapons when completing 'Old Comrades'.
Finish single player on any difficulty.
Spit on Barkov.
Kill all enemies at the Church, Clocktower, and Pool without anyone calling for backup.
Shut off the power to 4 buildings in 'Going Dark'.
Kill both soldiers with one shot in 'Hometown'.
Stop three APCs with Hadir's sniper rifle.
Shoot the driver of the suicide truck.
Destroy 4 trucks with 4 drone strikes before they reach the end of their path in 'The Embassy'.
Kill an enemy with a direct hit from a smoke grenade.
Complete 'Clean House' without being hit using one bullet per threat.
Take down a flying helicopter with a molotov.
Crash a helicopter by shooting the pilot.
Only use one cinder block and bring it to the end of 'Embedded'.
Kill all the enemies in the 'Embedded' field of dead bodies.
Do not injure any civilians in 'Piccadilly'.
Neutralize the 'Fog of War' machine gun with a frag grenade.