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CVE-2021-20239

Status: ModifiedLow (3.3)—

A flaw was found in the Linux kernel in versions before 5.4.92 in the BPF protocol. This flaw allows an attacker with a local account to leak information about kernel internal addresses. The highest threat from this vulnerability is to confidentiality.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (3)

Fedoraproject — FedoraLinux — Linux KernelRedhat — Enterprise Linux

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2021-20239",
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          "vectorString": "AV:L/AC:L/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
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          "accessComplexity": "LOW",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
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  "lastModified": "2026-06-17T03:33:31.780",
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