Vulnerability-Lookup

FKIE_CVE-2021-20239

Vulnerability from fkie_nvd - Published: 2021-05-28 11:15 - Updated: 2026-06-17 03:33

Severity

3.3 (Low) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Summary

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.

References

	URL	Tags
	secalert@redhat.com	https://bugzilla.redhat.com/show_bug.cgi?id=1923636	Issue Tracking, Third Party Advisory
	af854a3a-2127-422b-91ae-364da2661108	https://bugzilla.redhat.com/show_bug.cgi?id=1923636	Issue Tracking, Third Party Advisory

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
redhat	enterprise_linux	5.0
redhat	enterprise_linux	6.0
redhat	enterprise_linux	8.0
fedoraproject	fedora	33

JSON

To clipboard

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  "affected": [
    {
      "affectedData": [
        {
          "product": "kernel",
          "vendor": "n/a",
          "versions": [
            {
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              "version": "kernel 5.4.92"
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    }
  ],
  "id": "CVE-2021-20239",
  "lastModified": "2026-06-17T03:33:31.780",
  "metrics": {
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        "baseSeverity": "LOW",
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          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 2.1,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "NONE",
          "vectorString": "AV:L/AC:L/Au:N/C:P/I:N/A:N",
          "version": "2.0"
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        "obtainAllPrivilege": false,
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          "scope": "UNCHANGED",
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  "published": "2021-05-28T11:15:08.003",
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  "vulnStatus": "Modified",
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  ]
}

CVE-2021-20239 (GCVE-0-2021-20239)

Vulnerability from cvelistv5 – Published: 2021-05-28 10:42 – Updated: 2024-08-03 17:37

Summary

Severity

No CVSS data available.

CWE

CWE-822 - >CWE-200

Assigner

redhat redhat root

References

1 reference

URL	Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1923636	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
n/a	kernel	Affected: kernel 5.4.92

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.