mirror of
https://github.com/mukul975/Anthropic-Cybersecurity-Skills.git
synced 2026-06-11 05:34:55 +03:00
mukul975
c21af3347e
- Add scripts/agent.py and references/api-reference.md to all remaining skills - Update all 648 LICENSE files: copyright now reads 'Mahipal' - Add implementing-security-monitoring-with-datadog (new skill with full anatomy) - All 649 skills now have: SKILL.md, LICENSE, scripts/agent.py, references/api-reference.md
99 lines
2.2 KiB
Markdown
99 lines
2.2 KiB
Markdown
# API Reference: Broken Link Hijacking
|
|
|
|
## Concept
|
|
Broken Link Hijacking (BLH) occurs when a website links to external resources
|
|
that no longer exist. An attacker can register the expired resource (domain,
|
|
GitHub repo, npm package) to serve malicious content via the trusted site.
|
|
|
|
## Hijackable Platforms
|
|
|
|
| Platform | Hijack Vector |
|
|
|----------|---------------|
|
|
| GitHub | Register abandoned username/repo |
|
|
| npm | Publish unclaimed package name |
|
|
| PyPI | Register unclaimed package |
|
|
| Twitter/X | Claim abandoned handle |
|
|
| BitBucket | Register abandoned team/repo |
|
|
| Custom domain | Register expired domain |
|
|
|
|
## Python requests — Link Checking
|
|
|
|
### HEAD Request
|
|
```python
|
|
import requests
|
|
resp = requests.head(url, timeout=10, allow_redirects=True, verify=False)
|
|
# 404 = broken link, potential hijack
|
|
```
|
|
|
|
### Connection Error = Domain Takeover
|
|
```python
|
|
try:
|
|
requests.head(url, timeout=5)
|
|
except requests.ConnectionError:
|
|
print("Domain may be unregistered - takeover possible")
|
|
```
|
|
|
|
## HTML Link Extraction
|
|
|
|
### Regex Patterns
|
|
```python
|
|
import re
|
|
# href links
|
|
re.finditer(r'href=["\']([^"\']+)', html)
|
|
# src links
|
|
re.finditer(r'src=["\']([^"\']+)', html)
|
|
```
|
|
|
|
## Domain Availability Check
|
|
|
|
### WHOIS Lookup
|
|
```bash
|
|
whois expired-domain.com
|
|
# "No match for" = available for registration
|
|
```
|
|
|
|
### DNS Check
|
|
```bash
|
|
dig expired-domain.com +short
|
|
# Empty = no DNS records (likely available)
|
|
```
|
|
|
|
## GitHub API — Check Username Availability
|
|
|
|
### Check user exists
|
|
```http
|
|
GET https://api.github.com/users/username
|
|
```
|
|
- 200 = exists
|
|
- 404 = available for registration
|
|
|
|
### Check repo exists
|
|
```http
|
|
GET https://api.github.com/repos/owner/repo
|
|
```
|
|
|
|
## npm Registry — Check Package
|
|
|
|
```http
|
|
GET https://registry.npmjs.org/package-name
|
|
```
|
|
- 200 = exists
|
|
- 404 = available for registration
|
|
|
|
## Subdomain Takeover Indicators
|
|
|
|
### CNAME to Unclaimed Service
|
|
```bash
|
|
dig CNAME old-service.example.com
|
|
# old-service.example.com. CNAME unregistered.herokuapp.com.
|
|
```
|
|
|
|
### Common Vulnerable Services
|
|
| Service | Indicator |
|
|
|---------|-----------|
|
|
| GitHub Pages | 404 "There isn't a GitHub Pages site here" |
|
|
| Heroku | "No such app" |
|
|
| AWS S3 | "NoSuchBucket" |
|
|
| Azure | "404 Web Site not found" |
|
|
| Shopify | "Sorry, this shop is currently unavailable" |
|