> For the complete documentation index, see [llms.txt](https://capcap-1.gitbook.io/capcap/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://capcap-1.gitbook.io/capcap/readme/ctf-modules/exploitation/password-attacks/cracking-protected-files.md).

# Cracking Protected Files

### Cracking Protected Files & Archives

#### Hunting for Encrypted Files

```bash
# Search for commonly encrypted file types
for ext in $(echo ".xls .xls* .xltx .od* .doc .doc* .pdf .pot .pot* .pp*");do echo -e "\nFile extension: " $ext; find / -name *$ext 2>/dev/null | grep -v "lib\|fonts\|share\|core" ;done
```

#### Hunting for SSH Keys

SSH keys have no standard extension — find them by content:

```bash
grep -rnE '^\-{5}BEGIN [A-Z0-9]+ PRIVATE KEY\-{5}$' /* 2>/dev/null
```

Check if an SSH key is passphrase-protected:

```bash
# No passphrase — outputs public key directly
ssh-keygen -yf ~/.ssh/id_ed25519

# Has passphrase — prompts for it
ssh-keygen -yf ~/.ssh/id_rsa
```

> Old PEM format keys show `Proc-Type: 4,ENCRYPTED` in the header. Modern keys look the same whether encrypted or not — always test with `ssh-keygen -yf`.

***

#### Cracking Encrypted SSH Keys

```bash
# Extract hash from SSH key
ssh2john SSH.private > ssh.hash

# Crack it
john --wordlist=/usr/share/wordlists/rockyou.txt ssh.hash

# Show result
john ssh.hash --show
```

***

#### Cracking Password-Protected Documents

**Microsoft Office (docx, xlsx, pptx etc.):**

```bash
office2john.py Protected.docx > protected.hash
john --wordlist=/usr/share/wordlists/rockyou.txt protected.hash
john protected.hash --show
```

**PDF:**

```bash
pdf2john.py PDF.pdf > pdf.hash
john --wordlist=/usr/share/wordlists/rockyou.txt pdf.hash
john pdf.hash --show
```

**Archives (ZIP, RAR):**

```bash
zip2john archive.zip > zip.hash
john --wordlist=/usr/share/wordlists/rockyou.txt zip.hash

rar2john archive.rar > rar.hash
john --wordlist=/usr/share/wordlists/rockyou.txt rar.hash
```

***

#### Universal Workflow

```bash
# 1. Find the right *2john tool
locate *2john*

# 2. Extract hash
<tool>2john <file> > file.hash

# 3. Crack
john --wordlist=/usr/share/wordlists/rockyou.txt file.hash

# 4. Show result
john file.hash --show
```


---

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