Liebler was reported missing and his body was found the next day.
Friend Ben Manvel told The Desert Sun that Liebler, aside from being a long-time college professor, did work for the CIA developing secret codes for stealth communication, and was in Palm Springs working with a local think tank.
University officials and identification found on the body confirmed the man's identity. On Thursday he had not been officially identified by the Riverside County Coroner's office.
The body of another hiker was found in the same area on Sunday. The identity has not been determined.