Is there a public exploit for CVE-2021-4204?

Yes. Proof-of-concept code for CVE-2021-4204 has been published publicly.

Is there a proof of concept for CVE-2021-4204?

Yes — 1 proof-of-concept entry is linked on this page, from public repositories and community submissions. They are listed for authorised testing only.

What does CVE-2021-4204 affect?

CVE-2021-4204 affects n/a Kernel.

— Unscored

An out-of-bounds (OOB) memory access flaw was found in the Linux kernel's eBPF due to an Improper Input Validation.

CVE-2021-4204

An out-of-bounds (OOB) memory access flaw was found in the Linux kernel's eBPF due to an Improper Input Validation. This flaw allows a local attacker with a special privilege to crash the system or leak internal information.

Proof-of-concept code is published

Public PoC

Public PoCtr3ee/CVE-2021-420462 stars

Signals come from Exploit-DB, Metasploit, Nuclei and published proof-of-concept repositories. Their absence means nothing was found, not that nothing exists.

Assessment

CVSS: Not yet scored
Severity: Unscored
EPSS: 1.25% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Public PoC
Published: 24 August 2022
Last updated: 2 November 2026
Affected: n/a · Kernel
Assigner: redhat

At the source

EUVD (ENISA)

References

Community proofs of concept

No community proof of concept yet. If you have one for a published vulnerability and the right to share it, add it below — it will appear here once reviewed.

Submit a proof of concept

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Before you submit * This vulnerability is already publicly disclosed (it has a published CVE). This material comes only from testing I was authorised to perform. I have the legal right to publish this content and am not breaching any agreement by doing so. It contains no live credentials, personal data, or anything targeting systems I am not authorised to test. I understand it will be reviewed before it appears publicly and may be rejected. I agree to the submission terms.

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Query this programmatically

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curl https://cve.zerocrew.in/api/cve/CVE-2021-4204