*Published exclusively for users wanting clarity on the mysterious CVE-2021-0447.*

Introduction

Imagine searching for details on a security vulnerability, only to find out that it officially…doesn’t exist. That’s what happens with CVE-2021-0447. If you’re looking for real code samples, exploits, or even a detailed description related to this CVE, you’ll be disappointed, as this number was rejected or withdrawn by its assigning authority. So, what does that mean for developers and security researchers? In this long-read, we’ll explain the rejection status, how CVE processing works, and show what would usually be included if this CVE were valid.

What Is CVE-2021-0447?

CVE stands for Common Vulnerabilities and Exposures. Each published vulnerability has a unique ID, like CVE-2021-0447, which allows people to track and discuss issues in software everywhere.

Official source for this CVE:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-0447

Here’s what the CVE site says

> REJECTED — This candidate has been withdrawn by its CVE Numbering Authority (CNA). Further information may be available at NVD

The CNA (CVE Numbering Authority) decided it shouldn’t be listed for another reason.

Once rejected, the CVE entry remains as a placeholder, but no technical detail is ever published.

To help everyone understand, here’s an example layout for a real CVE

// Example of a typical CVE vulnerability (NOT related to CVE-2021-0447)
if (userInput != null && userInput.equals("admin")) {
    // grant privileges
}

Exploit scenario

A user could craft input to always pass this check.

References

- Android Security Bulletin
- NIST NVD

The fix addressed a non-vulnerability.

For CVE-2021-0447, the assigning authority (possibly Android/Google) reviewed the initial report, determined it was unnecessary, and updated the status to REJECTED before details were released.

What if You See “Exploit” Code for CVE-2021-0447?

Be wary: since this CVE was never published as a real vulnerability, any sample code or so-called “exploit” posted online with this ID is not legitimate. For education, here's a dummy code snippet showing what you will not find associated with CVE-2021-0447:

// There is no real vulnerability assigned to CVE-2021-0447
public void doSomething() {
    // safe, nothing here!
}

Don’t panic if you see a tool flag this number.

- Confirm using the official CVE site or NVD.

Conclusion

CVE-2021-0447 never described a real vulnerability.
If you see it come up in news, code, or software reports, it is best regarded as a non-event. Always check the official references first!

Learn more:
- What Does CVE Rejected Mean? (MITRE)
- CVE List

Stay smart and double-check your security sources.

Timeline

Published on: 01/17/2025 23:15:12 UTC