Hashcat Basics

Hashcat is a powerful password recovery tool that supports various hashing algorithms and cracking methods. Here are some essential Hashcat commands and concepts that can help you be successful:

1. Basic Syntax

The general syntax for running Hashcat:

hashcat -m [hash_type] -a [attack_mode] -o [output_file] [hash_file] [wordlist_or_rules]

-m: Hash type (e.g., MD5, SHA1, bcrypt).
-a: Attack mode (e.g., dictionary, brute-force).
-o: Output file for cracked hashes.
[hash_file]: File containing the hashes.
[wordlist_or_rules]: Wordlist or rules file (depends on the mode).

2. Important Hashcat Options

-m (Hash Type): Defines the type of hash to crack.
Example:
- 0 for MD5
- 100 for SHA1
- 3200 for bcrypt
  Full list: Hashcat Hash Types
-a (Attack Mode): Defines the cracking method:
- 0: Dictionary attack
- 1: Combination attack
- 3: Brute-force attack
- 6: Hybrid dictionary + mask
- 7: Hybrid mask + dictionary
--force: Forces Hashcat to run on unsupported devices (use cautiously).
--session [name]: Saves the current session so you can resume later.
--restore: Resumes a saved session.
--show: Displays cracked hashes from the output file.

3. Example Commands

Dictionary Attack

hashcat -m 0 -a 0 -o cracked.txt hashes.txt rockyou.txt

-m 0: MD5 hash type.
-a 0: Dictionary attack.
hashes.txt: File with hashes.
rockyou.txt: Wordlist file.

Brute-Force Attack

hashcat -m 0 -a 3 -o cracked.txt hashes.txt ?a?a?a?a

?a: Represents any printable ASCII character.
You can adjust the length (e.g., ?a?a?a?a?a for 5 characters).

Combination Attack

hashcat -m 0 -a 1 -o cracked.txt hashes.txt wordlist1.txt wordlist2.txt

Combines words from wordlist1.txt and wordlist2.txt.

Hybrid Dictionary + Mask Attack

hashcat -m 100 -a 6 -o cracked.txt hashes.txt rockyou.txt ?d?d?d

Appends three digits (?d?d?d) to each word in the dictionary.

Hybrid Mask + Dictionary Attack

hashcat -m 100 -a 7 -o cracked.txt hashes.txt ?d?d rockyou.txt

Prepends two digits (?d?d) to each word in the dictionary.

4. Customizing Masks

Mask characters allow you to specify the charset:

?l: Lowercase letters (a-z).
?u: Uppercase letters (A-Z).
?d: Digits (0-9).
?s: Special characters.
?a: All of the above.
Example: ?u?l?l?l?d?d (e.g., Aaaa11).

5. Speed Optimization

--optimized-kernel-enable: Speeds up attacks on simpler hash algorithms.
-w: Workload profile:
- -w 1: Low power (used for multitasking).
- -w 4: High power (max performance).

6. Rules

Rules modify the words in your wordlist dynamically:

hashcat -m 0 -a 0 -o cracked.txt hashes.txt -r rules/best64.rule

Popular rule files include best64.rule and d3ad0ne.rule.

7. Session Management

Save session:

hashcat --session mysession -m 0 -a 3 hashes.txt ?a?a?a

Restore session:
```
hashcat --restore --session mysession
```

8. Benchmarking

Test your system's performance with different hash types:

hashcat -b

9. GPU Configuration

Ensure GPU acceleration is enabled:

hashcat -I

Use -D to select the device type:
- -D 1: Use CPU.
- -D 2: Use GPU.

Generate Hashes

Generate your own hashes using Python:

import hashlib

# MD5 hash
print(hashlib.md5(b'test').hexdigest())

# SHA1 hash
print(hashlib.sha1(b'test').hexdigest())

10. Tips for Success

Use the right hash type for your target.
Experiment with attack modes based on the scenario.
Leverage wordlists and rules for better results.
Use session management for long-running jobs.
Test your setup using the benchmark mode.
Keep your Hashcat updated for new features and improved performance.

LiteObject / demo-hashcat