A method, system and computer program product for securing decrypted files
in a shared environment. A filter driver in a kernel space may be
configured to control service requests to encrypted files stored in a
shared area, e.g., a shared directory on a disk unit, accessible by
multiple users. The filter driver may receive a service request to open
an encrypted document in the shared area issued from an authorized user.
Upon receiving the encrypted data, the filter driver may decrypt the
encrypted data. The filter driver may subsequently store the decrypted
data in a file in a non-shared area, e.g., a non-shared directory. The
non-shared area may be accessible only by the authorized user that
requested access to the encrypted file. By storing the decrypted data in
a file in the non-shared area, a file once decrypted may be protected in
a file sharing environment.