SSH Server CBC Mode Ciphers Enabled

ID: ssh-cbc-mode-ciphers

Severity: low

Author: pussycat0x

Tags: js,enum,ssh,misconfig,network

Description

“SSH Server CBC Mode Ciphers Enabled” signifies that the SSH server supports Cipher Block Chaining (CBC) mode ciphers, which are known for potential vulnerabilities. This configuration poses a security risk, and it’s recommended to disable CBC ciphers in favor of more secure alternatives for enhanced protection during data transmission.

YAML Source

id: ssh-cbc-mode-ciphers

info:
  name: SSH Server CBC Mode Ciphers Enabled
  author: pussycat0x
  severity: low
  description: |
    "SSH Server CBC Mode Ciphers Enabled" signifies that the SSH server supports Cipher Block Chaining (CBC) mode ciphers, which are known for potential vulnerabilities. This configuration poses a security risk, and it's recommended to disable CBC ciphers in favor of more secure alternatives for enhanced protection during data transmission.
  reference:
    - https://www.tenable.com/plugins/nessus/70658
  metadata:
    verified: true
    max-request: 2
    shodan-query: product:"OpenSSH"
  tags: js,enum,ssh,misconfig,network

javascript:
  - pre-condition: |
      isPortOpen(Host,Port)
    code: |
      let m = require("nuclei/ssh");
      let c = m.SSHClient();
      let response = c.ConnectSSHInfoMode(Host, Port);
      Export(response);
    args:
      Host: "{{Host}}"
      Port: "22"

    matchers-condition: and
    matchers:
      - type: word
        words:
          - "client_to_server_ciphers"
          - "server_to_client_ciphers"
        condition: and

      - type: word
        words:
          - "aes128-cbc"
          - "aes192-cbc:"
          - "aes256-cbc"
          - "3des-cbc"
          - "blowfish-cbc"
          - "cast128-cbc"
        condition: or
# digest: 4a0a00473045022100d5257e4a89ebf2e497215370a90928abc06a2e397bad4d06161870963155d4c202200fa0fca3160b68f8cad75d2ddeb222cf6defec4d1b971de78fa0a818c10c5ea7:922c64590222798bb761d5b6d8e72950

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.

$ nuclei -u "URL" -t "javascript/misconfiguration/ssh/ssh-cbc-mode-ciphers.yaml"

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