Ghosts Checksum Fixer
A command-line checksum fixer for Call of Duty: Ghosts Savegame.svg files. Works on PC, Xbox 360, PS3, WiiU, and (theoretically) Xbox One and PS4.
If you are looking for a tool for MW2 or MW3, it can be found at https://github.com/HunterStanton/MWX-Checksum-Fixer
If you're looking for a tool for Call of Duty: Infinite Warfare, it can be found at https://github.com/HunterStanton/IW-Checksum-Fixer
I have no idea about other Call of Duty games (such as Modern Warfare Remastered, Advanced Warfare, or Black Ops 1/2). Call of Duty 4 and 5 do not use checksummed saves.
GhostsChecksumFixer.exe savegame.svg endian (big/little)
PS3, Xbox 360, and WiiU use BIG endian. PC, PS4, and XBox One use LITTLE endian.
After fixing, both the original and new checksums will be displayed for your reference.