VMware vCenter Server - Arbitrary File Upload

Exploited in the wild. Listed by CISA on 2021-11-03; known to be used by ransomware.

criticalseverity

9.8CVSS score

100%likelihood of exploitation, next 30 days

100%of all CVEs are less likely

Readycheck to confirm it

VMware vCenter Server contains an arbitrary file upload vulnerability in the Analytics service. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to execute code on vCenter Server by uploading a specially crafted file.

Impact

Allows an attacker to upload and execute arbitrary files on the target system

Fix

Apply the necessary security patches or updates provided by VMware

How to confirm it

Send: GET / ; POST /analytics/telemetry/ph/api/hyper/send?_c&_i=test
Positive when: status_code_1 == 200 and status_code_2 == 201 and contains(body_1, 'VMware vSphere') and content_length_2 == 0

Run it with nuclei: nuclei -id CVE-2021-22005 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-22005

info:
  name: VMware vCenter Server - Arbitrary File Upload
  author: PR3R00T
  severity: critical
  description: VMware vCenter Server contains an arbitrary file upload vulnerability in the Analytics service. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to execute code on vCenter Server by uploading a specially crafted file.
  impact: |
    Allows an attacker to upload and execute arbitrary files on the target system
  remediation: |
    Apply the necessary security patches or updates provided by VMware
  reference:
    - https://kb.vmware.com/s/article/85717
    - https://www.vmware.com/security/advisories/VMSA-2021-0020.html
    - https://core.vmware.com/vmsa-2021-0020-questions-answers-faq
    - https://nvd.nist.gov/vuln/detail/CVE-2021-22005
    - https://github.com/ARPSyndicate/kenzer-templates
  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-2021-22005
    cwe-id: CWE-22
    epss-score: 0.99999
    epss-percentile: 0.99998
    cpe: cpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
  metadata:
    max-request: 2
    vendor: vmware
    product: cloud_foundation
  tags: cve2021,cve,vmware,vcenter,fileupload,kev,intrusive,vkev,vuln

http:
  - raw:
      - |
        GET / HTTP/1.1
        Host: {{Hostname}}
      - |
        POST /analytics/telemetry/ph/api/hyper/send?_c&_i=test HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/json

        test_data

    matchers:
      - type: dsl
        dsl:
          - "status_code_1 == 200"
          - "status_code_2 == 201"
          - "contains(body_1, 'VMware vSphere')"
          - "content_length_2 == 0"
        condition: and

References

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