Cisco devices use a variety of password encryption methods, including:

Although it only affects Type 7, it is a basic step to protect other configuration text.

Treat configuration files and backups as highly sensitive data. Restrict access using strict permissions and encrypt stored configurations.

Hashing algorithms are designed as one-way mathematical functions. Unlike encryption systems (such as AES or RSA), which use a key to scramble data and another key to reverse it, hashing permanently discards data to create a fixed-length fingerprint. Because information is lost during the process, you cannot apply a mathematical formula to turn a Type 5 hash back into plain text. How "Recovery" Actually Works

A standard Type 5 string in a configuration file looks like this: enable secret 5 $1$mERr$hx5rOB7v6Xb8ubGO9Z8wz. Anatomy of the Hash String