OPNsense <=20.1.5 - Open Redirect

mediumseverity

6.1CVSS score

2.7%likelihood of exploitation, next 30 days

86%of all CVEs are less likely

Readycheck to confirm it

OPNsense through 20.1.5 contains an open redirect vulnerability via the url redirect parameter in the login page, which is not filtered. An attacker can redirect a user to a malicious site and possibly obtain sensitive information, modify data, and/or execute unauthorized operations.

Impact

Successful exploitation of this vulnerability could allow an attacker to redirect users to malicious websites, leading to phishing attacks or the disclosure of sensitive information.

Fix

Upgrade OPNsense to a version higher than 20.1.5 to mitigate the vulnerability.

How to confirm it

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

Run it with nuclei: nuclei -id CVE-2020-23015 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2020-23015

info:
  name: OPNsense <=20.1.5 - Open Redirect
  author: 0x_Akoko
  severity: medium
  description: OPNsense through 20.1.5 contains an open redirect vulnerability via the url redirect parameter in the login page, which is not filtered. An attacker can redirect a user to a malicious site and possibly obtain sensitive information, modify data, and/or execute unauthorized operations.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to redirect users to malicious websites, leading to phishing attacks or the disclosure of sensitive information.
  remediation: |
    Upgrade OPNsense to a version higher than 20.1.5 to mitigate the vulnerability.
  reference:
    - https://github.com/opnsense/core/issues/4061
    - https://nvd.nist.gov/vuln/detail/CVE-2020-23015
    - https://github.com/anonymous364872/Rapier_Tool
    - https://github.com/ARPSyndicate/kenzer-templates
    - https://github.com/StarCrossPortal/scalpel
  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-2020-23015
    cwe-id: CWE-601
    epss-score: 0.02677
    epss-percentile: 0.85923
    cpe: cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: opnsense
    product: opnsense
    shodan-query: http.title:"opnsense"
    fofa-query: title="opnsense"
    google-query: intitle:"opnsense"
  tags: cve2020,cve,redirect,opnsense,vuln

http:
  - method: GET
    path:
      - '{{BaseURL}}/?url=http://interact.sh'

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

References

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