Click Ranker vulnerable to cross-site scripting


Click Ranker <http://homepage2.nifty.com/goplace/> contains a stored cross-site scripting vulnerability (CWE-79) which allows unintentional script execution on the web browser of user who accesses a page ranking screen.

During the meeting of Committee for authorizing the disclosure of unresolved vulnerabilities held on January 22, 2021, it was judged that an advisory for this vulnerability shall be disclosed since all the criteria and conditions described below which are stated in Standards for Handling Vulnerability related Information of Software Products and Other and Information Security Early Warning Partnership Guideline have been satisfied.

1.The developer of the product is unreachable.
2.Existence of vulnerability has been verified.
3.Not disclosing this case may result in the risk that product users will have no means to know of the existence of the vulnerability in the product.
4.There are no particular reasons that would make disclosure inappropriate.
CVSS Severity (What is CVSS?)

CVSS V3 Severity:
Base Metrics 6.1 (Medium) [IPA Score]
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: Required
  • Scope: Changed
  • Confidentiality Impact: Low
  • Integrity Impact: Low
  • Availability Impact: None
CVSS V2 Severity:
Base Metrics 5.0 (Medium) [IPA Score]
  • Access Vector: Network
  • Access Complexity: Low
  • Authentication: None
  • Confidentiality Impact: None
  • Integrity Impact: Partial
  • Availability Impact: None
Affected Products

  • Click Ranker Ver.3.5


An arbitrary script may be executed on the web browser of the user who is accessing a website that uses Click Ranker.

[Consider stop using Click Ranker Ver.3.5]
Since the developer was unreachable, existence of any mitigations is unknown.
Vendor Information

CWE (What is CWE?)

  1. Cross-site Scripting(CWE-79) [IPA Evaluation]
CVE (What is CVE?)

  1. CVE-2021-20688

  1. JVN : JVN#93207949
  2. National Vulnerability Database (NVD) : CVE-2021-20688
Revision History

  • [2021/03/25]
      Web page was published