Is it safe to open a crypted file with a text editor

Question

Say I have files encrypted and I open them with a text editor, am I in risk of those files being copied in some temp memory ? I noticed this sentence in the introduction on truecrypt website

"Note that TrueCrypt never saves any decrypted data to a disk – it only stores them temporarily in RAM (memory). Even when the volume is mounted, data stored in the volume is still encrypted"

But do I understand it correctly ?

Answer 1

If a file stored in a TrueCrypt volume is opened in a text editor (or any application really), the decrypted file is temporarily stored in RAM. Once in RAM, another application could potentially copy the data if it can locate the files contents in memory. The feasibility of this is highly dependent on the operating system you're using though.

Also, the editor you've opened the decrypted file in may save a copy of it to a non-encrypted disk. Once you've opened a file in an application it can do anything it wants with the data, it doesn't matter where the data originally came from or in what form it was stored.

Last, depending on your operating system, the OS itself may leave traces of encrypted files. For example, Windows keeps a list of recently opened files, and while this doesn't leave decrypted file contents lying around, it does reveal the names of any files from the TrueCrypt volume that were opened.