ZDF
Sign inSign up

Vulnerabilities

Security incident · 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.

Published Aug 24, 2022 · catalog updated Nov 2, 2026 · linux kernel

Last checked Nov 6, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2021-4204. EPSS is 1.24%. Act only if a listed version of linux kernel is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
High7.1
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
1.24%
Remediation
Version ranges on file
Affected products
cpe debian/debian linux · cpe linux/linux kernel · cpe netapp/h300s firmware · cpe netapp/h410s firmware · cpe netapp/h500s firmware · cpe netapp/h700s firmware

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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe debian/debian linux11.0
  • cpe linux/linux kernel5.8.0
  • cpe linux/linux kernel< 5.8.0
  • cpe netapp/h300s firmwareversion unspecified
  • cpe netapp/h410s firmwareversion unspecified
  • cpe netapp/h500s firmwareversion unspecified
  • cpe netapp/h700s firmwareversion unspecified
  • cpe redhat/enterprise linux9.0

How to fix CVE-2021-4204

  • Upgrade

    CVE-2021-4204 lists a fix boundary at 5.8.0. Compare the installed build with that boundary before you change production.

  • Version check

    Affected < 5.8.0

  • Advisory

    Open the cve_org record and follow its fix.

  • Official advisories

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2021-4204. EPSS is 1.24%. Act only if a listed version of linux kernel is installed.

Which versions are affected?

Compare what you have installed with debian/debian linux 11.0; linux/linux kernel 5.8.0; linux/linux kernel < 5.8.0; redhat/enterprise linux 9.0. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-119: Buffer Overflow; CWE-20: Improper Input Validation. EPSS 1.24%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Aug 24, 2022 · NIST NVD

    Detected

    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.

  2. Nov 2, 2026 · NIST NVD

    Updated

    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.

Sources

  • CVE.orgVulnerability recordCVE-2021-4204

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-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.

    nvd.nist.gov

References

Freshness

Last verified in this catalog Nov 6, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • CVE.orgNov 4, 2026
  • NIST NVDNov 3, 2026