Cisco Password Types Explained: Type 0 vs 5 vs 8 vs 9 (2026 Security Guide)
If you manage Cisco routers or switches, you’ve likely seen configuration lines like:
enable secret 5 $1$abcd$...
username admin secret 9 $9$...
password 7 0822455D0A16
What do these numbers mean?
More importantly — which Cisco password type is secure in 2026?
In this guide, we break down all Cisco password types (0–9), compare their security levels, and explain which one you should use on modern Cisco IOS and IOS-XE devices.
For a technical reference overview of how each algorithm works internally, you can also review this detailed breakdown of the six Cisco password types.
What Are Cisco Password Types?
Cisco IOS and IOS-XE support multiple password storage formats. These are commonly referred to as:
Type 0
Type 4
Type 5
Type 7
Type 8
Type 9
(+ Type 6 for special reversible encryption use cases)
Each type represents a different encryption or hashing mechanism.
Cisco Password Types Comparison Table
Detailed Explanation of Each Cisco Password Type
Type 0 – Plaintext Password
Example:
username admin password mypassword
Type 0 stores the password in clear text inside the configuration file.
✔ Easy to read
❌ Completely insecure
Never use enable password. Always use enable secret.
Type 7 – Reversible Encryption
Generated by:
service password-encryption
Type 7 is not true encryption. It uses a reversible cipher and can be decoded instantly using public tools.
❌ Not secure
❌ Should be removed from production configs
Type 4 – Broken SHA-256 Implementation
Introduced around 2013, Type 4 attempted to improve security but was implemented incorrectly (no salt, single iteration).
Cisco deprecated it due to cryptographic weakness.
❌ Do not use
Type 5 – MD5-Based Hashing
Example:
enable secret 5 $1$abcd$...
Type 5 uses MD5 with 1000 iterations and a 32-bit salt.
While once considered secure, modern GPU hardware can crack MD5-based hashes at high speed.
⚠ Acceptable only on older hardware that does not support newer types
Type 8 – PBKDF2-HMAC-SHA256
Configured using:
username admin algorithm-type sha256 secret StrongPassword123!
Type 8 uses:
SHA-256
20,000 iterations
80-bit salt
✔ Strong enterprise-grade hashing
✔ Suitable for compliance environments
Type 9 – Scrypt (Best Practice)
Configured using:
username admin algorithm-type scrypt secret StrongPassword123!
Type 9 uses Scrypt, a memory-hard algorithm designed to resist GPU and ASIC-based cracking.
✔ Highest security level in Cisco IOS-XE
✔ Recommended for all modern deployments
How to Change Cisco Password Type to Type 9
To upgrade your privileged password:
enable algorithm-type scrypt secret StrongPassword123!
To upgrade a local user:
username admin algorithm-type scrypt secret StrongPassword123!
After applying, verify with:
show running-config | include username
Cisco Password Migration Checklist
Before upgrading password types:
Confirm device IOS / IOS-XE version supports Type 8 or 9
Test on non-production equipment
Ensure automation scripts generate correct hash types
Remove all legacy Type 0, 4, and 7 entries
Frequently Asked Questions
Is Cisco Type 5 secure?
Type 5 (MD5-based) is considered legacy. It is not recommended for modern security standards but may still be used on older devices.
What is the default Cisco password type in IOS-XE?
Modern IOS-XE platforms support and commonly use stronger algorithms such as Type 8 or Type 9 when configured with algorithm-type.
Should I use Type 8 or Type 9?
Use Type 9 (Scrypt) for maximum resistance to brute-force attacks.
Use Type 8 (PBKDF2) if regulatory or compliance standards require it.
What is Type 6 used for?
Type 6 is AES-based reversible encryption used for service credentials such as BGP, OSPF, or RADIUS shared secrets.
Final Recommendation (2026)
If your Cisco configuration still contains:
password 7enable secret 5secret 4
It is time to modernize.
For all new deployments on IOS-XE platforms, Type 9 (Scrypt) should be your default security baseline.
Password hashing is one of the simplest infrastructure improvements you can implement — yet it significantly increases resistance against offline configuration attacks.
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