When browsing security databases or working with vulnerability reports, you may come across certain CVE identifiers that seem to have no technical details, patches, or exploits. One such example is CVE-2021-41858. In this post, I’ll break down what’s known about CVE-2021-41858, why it was rejected, and what it means when a CVE is marked “unused”. This information is exclusive to this write-up and aims to clarify a confusing part of vulnerability management.

What is CVE-2021-41858?

CVE-2021-41858 is a unique identifier from the Common Vulnerabilities and Exposures (CVE) system. The CVE system catalogs publicly known cybersecurity vulnerabilities, allowing them to be referenced consistently.

But, in some cases—such as with CVE-2021-41858—the identifier was published but no associated vulnerability exists.

> "REJECT Reason: This is unused."

That’s it. There are no technical details, no affected products, no severity rating, and crucially, no patch or fix.

Why Do CVEs Get REJECTED?

CVEs are sometimes requested in error, reserved for issues that are later found not to be real vulnerabilities, or they might refer to reports that are later merged into another CVE. When this happens and the CVE is never assigned to an actual security bug, it’s rejected.

When a CVE is rejected, you'll usually see a note like

REJECT Reason: This is unused.

In the CVE Record, it looks like this

{
  "cve": "CVE-2021-41858",
  "state": "REJECTED",
  "description": {
    "description_data": [
      {
        "lang": "en",
        "value": "This candidate has been revoked and is unused."
      }
    ]
  }
}

Implications: Should You Worry?

No. A rejected CVE like CVE-2021-41858 represents *no actual vulnerability*.

No Patch Needed: Vendors will NOT release a fix, as there’s nothing broken.

- No Impact on Your Systems: Security scanners may flag it, but you can safely ignore it if the status is REJECTED.

No official vendor bulletins.

If you ever see code or claims regarding CVE-2021-41858, they are not legitimate.

Quick Example: Handling CVEs in Reports

If you're running a vulnerability scan, your report might automatically include CVE references. Here’s a simple Python snippet to filter out rejected CVEs based on state (pseudocode):

import json

def is_rejected(cve_record):
    return cve_record.get('state') == "REJECTED"

# Example CVE record from database or API
cve_record = {
    "cve": "CVE-2021-41858",
    "state": "REJECTED",
    "description": { ... }
}

if is_rejected(cve_record):
    print("Ignore this CVE; it's unused.")
else:
    print("CVE potentially valid, investigate further.")

References

- CVE-2021-41858 at cve.org
- CVE FAQ: What does REJECT mean?
- NVD Record

Final Thoughts

CVE-2021-41858 is a perfect example of a CVE that was created but never assigned to an actual security problem. When you see a rejected and unused CVE like this, you can simply move on—no patching or mitigation is needed.

The world of vulnerability management has its quirks, and knowing what these “unused” identifiers mean can save you time and stress during security reviews.


*Stay secure, and remember to double-check your CVE sources!*

Timeline

Published on: 02/23/2024 21:15:10 UTC
Last modified on: 09/04/2025 00:48:06 UTC