Noptin < 1.6.5 - Open Redirect

mediumseverity

6.1CVSS score

2.3%likelihood of exploitation, next 30 days

84%of all CVEs are less likely

Readycheck to confirm it

Noptin < 1.6.5 is susceptible to an open redirect vulnerability. The plugin does not validate the "to" parameter before redirecting the user to its given value, leading to an open redirect issue.

Impact

An attacker can trick users into visiting malicious websites, leading to phishing attacks.

Fix

Update to Noptin plugin version 1.6.5 or later.

How to confirm it

Send: GET {{BaseURL}}/?noptin_ns=email_click&to=https://interact.sh
Positive when: matches in header /(?m)^(?:Location\s*?:\s*?)(?:https?:\/\/|\/\/|\/\\\\|\/\\)(?:[a-zA-Z0-9\-_\.@]*…/

Run it with nuclei: nuclei -id CVE-2021-25033 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2021-25033

info:
  name: Noptin < 1.6.5 - Open Redirect
  author: dhiyaneshDk
  severity: medium
  description: Noptin < 1.6.5 is susceptible to an open redirect vulnerability. The plugin does not validate the "to" parameter before redirecting the user to its given value, leading to an open redirect issue.
  impact: |
    An attacker can trick users into visiting malicious websites, leading to phishing attacks.
  remediation: |
    Update to Noptin plugin version 1.6.5 or later.
  reference:
    - https://wpscan.com/vulnerability/c2d2384c-41b9-4aaf-b918-c1cfda58af5c
    - https://plugins.trac.wordpress.org/changeset/2639592
    - https://nvd.nist.gov/vuln/detail/CVE-2021-25033
    - https://github.com/ARPSyndicate/kenzer-templates
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cve-id: CVE-2021-25033
    cwe-id: CWE-601
    epss-score: 0.02303
    epss-percentile: 0.83472
    cpe: cpe:2.3:a:noptin:noptin:*:*:*:*:*:wordpress:*:*
  metadata:
    max-request: 1
    vendor: noptin
    product: noptin
    framework: wordpress
  tags: cve2021,cve,wp,wpscan,wordpress,redirect,wp-plugin,noptin,vuln,vkev

http:
  - method: GET
    path:
      - "{{BaseURL}}/?noptin_ns=email_click&to=https://interact.sh"

    matchers:
      - type: regex
        part: header
        regex:
          - '(?m)^(?:Location\s*?:\s*?)(?:https?:\/\/|\/\/|\/\\\\|\/\\)(?:[a-zA-Z0-9\-_\.@]*)interact\.sh\/?(\/|[^.].*)?$' # https://regex101.com/r/L403F0/1

References

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