Microsoft SharePoint - Remote Code Execution

highseverity

8.6CVSS score

71.1%likelihood of exploitation, next 30 days

99%of all CVEs are less likely

Readycheck to confirm it

Microsoft SharePoint is vulnerable to a remote code execution when the software fails to check the source markup of an application package.

Impact

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected system, potentially leading to a complete compromise of the SharePoint server.

Fix

Apply the latest security updates provided by Microsoft to address this vulnerability.

How to confirm it

Send: GET {{BaseURL}}
Positive when: matches /15\.0\.0\.(4571|5275|4351|5056)/ AND matches in header /(?i)(Microsoftsharepointteamservices:)/ AND status 200 or 201

Run it with nuclei: nuclei -id CVE-2020-16952 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2020-16952

info:
  name: Microsoft SharePoint - Remote Code Execution
  author: dwisiswant0
  severity: high
  description: Microsoft SharePoint is vulnerable to a remote code execution when the software fails to check the source markup of an application package.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected system, potentially leading to a complete compromise of the SharePoint server.
  remediation: |
    Apply the latest security updates provided by Microsoft to address this vulnerability.
  reference:
    - https://srcincite.io/pocs/cve-2020-16952.py.txt
    - https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16952
    - https://github.com/rapid7/metasploit-framework/blob/1a341ae93191ac5f6d8a9603aebb6b3a1f65f107/documentation/modules/exploit/windows/http/sharepoint_ssi_viewstate.md
    - https://nvd.nist.gov/vuln/detail/CVE-2020-16952
    - https://github.com/ARPSyndicate/cvemon
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
    cvss-score: 8.6
    cve-id: CVE-2020-16952
    cwe-id: CWE-346
    epss-score: 0.71095
    epss-percentile: 0.99412
    cpe: cpe:2.3:a:microsoft:sharepoint_enterprise_server:2016:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: microsoft
    product: sharepoint_enterprise_server
  tags: cve,cve2020,msf,sharepoint,iis,microsoft,ssi,rce,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}"

    matchers-condition: and
    matchers:
      - type: regex
        part: body
        regex:
          - "15\\.0\\.0\\.(4571|5275|4351|5056)"
          - "16\\.0\\.0\\.(10337|10364|10366)"
          # - "16.0.10364.20001"
        condition: or

      - type: regex
        part: header
        regex:
          - "(?i)(Microsoftsharepointteamservices:)"

      - type: status
        status:
          - 200
          - 201
        condition: or

References

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