BillQuick Web Suite SQL Injection

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

criticalseverity

9.8CVSS score

75.2%likelihood of exploitation, next 30 days

100%of all CVEs are less likely

Readycheck to confirm it

BQE BillQuick Web Suite 2018 through 2021 before 22.0.9.1 allows SQL injection for unauthenticated remote code execution. Successful exploitation can include the ability to execute arbitrary code as MSSQLSERVER$ via xp_cmdshell.

Impact

Successful exploitation of this vulnerability can lead to unauthorized access, data leakage, and potential compromise of the entire system.

Fix

Apply the latest security patches and updates provided by the vendor to fix the SQL Injection vulnerability in the BillQuick Web Suite.

How to confirm it

Send: GET / ; POST /
Positive when: contains "System.Data.SqlClient.SqlException" and "Incorrect syntax near" and "_ACCOUNTLOCKED"

Run it with nuclei: nuclei -id CVE-2021-42258 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-42258

info:
  name: BillQuick Web Suite SQL Injection
  author: dwisiswant0
  severity: critical
  description: BQE BillQuick Web Suite 2018 through 2021 before 22.0.9.1 allows SQL injection for unauthenticated remote code execution. Successful exploitation can include the ability to execute arbitrary code as MSSQLSERVER$ via xp_cmdshell.
  impact: |
    Successful exploitation of this vulnerability can lead to unauthorized access, data leakage, and potential compromise of the entire system.
  remediation: |
    Apply the latest security patches and updates provided by the vendor to fix the SQL Injection vulnerability in the BillQuick Web Suite.
  reference:
    - https://www.huntress.com/blog/threat-advisory-hackers-are-exploiting-a-vulnerability-in-popular-billing-software-to-deploy-ransomware
    - https://nvd.nist.gov/vuln/detail/CVE-2021-42258
    - https://github.com/ARPSyndicate/kenzer-templates
    - https://github.com/Ostorlab/KEV
    - https://github.com/Ostorlab/known_exploited_vulnerbilities_detectors
  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-2021-42258
    cwe-id: CWE-89
    epss-score: 0.75182
    epss-percentile: 0.99514
    cpe: cpe:2.3:a:bqe:billquick_web_suite:*:*:*:*:*:*:*:*
  metadata:
    max-request: 2
    vendor: bqe
    product: billquick_web_suite
  tags: cve2021,cve,sqli,billquick,kev,bqe,vkev,vuln

http:
  - raw:
      - |
        GET / HTTP/1.1
        Host: {{Hostname}}
      - |
        POST / HTTP/1.1
        Host: {{Hostname}}
        Referer: {{BaseURL}}
        Origin: {{RootURL}}
        Content-Type: application/x-www-form-urlencoded

        __EVENTTARGET=cmdOK&__EVENTARGUMENT=&__VIEWSTATE={{url_encode("{{VS}}")}}&__VIEWSTATEGENERATOR={{url_encode("{{VSG}}")}}&__EVENTVALIDATION={{url_encode("{{EV}}")}}&txtID=uname%27&txtPW=passwd&hdnClientDPI=96

    matchers:
      - type: word
        part: body
        words:
          - "System.Data.SqlClient.SqlException"
          - "Incorrect syntax near"
          - "_ACCOUNTLOCKED"
        condition: and

    extractors:
      - type: xpath
        name: VS
        internal: true
        xpath:
          - "/html/body/form/div/input[@id='__VIEWSTATE']"
        attribute: value

      - type: xpath
        name: VSG
        internal: true
        xpath:
          - "/html/body/form/div/input[@id='__VIEWSTATEGENERATOR']"
        attribute: value

      - type: xpath
        name: EV
        internal: true
        xpath:
          - "/html/body/form/div/input[@id='__EVENTVALIDATION']"
        attribute: value

References

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