Vulnerability-Lookup

FKIE_CVE-2021-26318

Vulnerability from fkie_nvd - Published: 2021-10-13 19:15 - Updated: 2026-06-17 03:43

Severity

4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Summary

A timing and power-based side channel attack leveraging the x86 PREFETCH instructions on some AMD CPUs could potentially result in leaked kernel address space information.

References

	URL	Tags
	psirt@amd.com	https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1017	Vendor Advisory
	af854a3a-2127-422b-91ae-364da2661108	https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1017	Vendor Advisory

Impacted products

Vendor	Product	Version
amd	athlon_firmware	-
amd	athlon	-
amd	athlon_pro_firmware	-
amd	athlon_pro	-
amd	epyc_firmware	-
amd	epyc	-
amd	ryzen_firmware	-
amd	ryzen	-
amd	ryzen_pro_firmware	-
amd	ryzen_pro	-

JSON

To clipboard

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          "product": "All supported processors",
          "vendor": "AMD",
          "versions": [
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    },
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      "lang": "es",
      "value": "Un ataque de canal lateral basado en el tiempo y la energ\u00eda aprovechando las instrucciones x86 PREFETCH en algunas CPUs de AMD podr\u00eda potencialmente resultar en una filtraci\u00f3n de informaci\u00f3n del espacio de direcciones del kernel"
    }
  ],
  "id": "CVE-2021-26318",
  "lastModified": "2026-06-17T03:43:06.570",
  "metrics": {
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        "baseSeverity": "LOW",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 1.9,
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          "integrityImpact": "NONE",
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  "published": "2021-10-13T19:15:07.360",
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    },
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  "vulnStatus": "Modified",
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}

CVE-2021-26318 (GCVE-0-2021-26318)

Vulnerability from cvelistv5 – Published: 2021-10-13 18:29 – Updated: 2024-09-16 16:48

Title

Side-channels Related to the x86 PREFETCH Instruction

Summary

A timing and power-based side channel attack leveraging the x86 PREFETCH instructions on some AMD CPUs could potentially result in leaked kernel address space information.

Severity

No CVSS data available.

CWE

CWE-208 - Information Exposure Through Timing Discrepancy

Assigner

AMD mitre root

References

1 reference

URL	Tags
https://www.amd.com/en/corporate/product-security…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
AMD	All supported processors	Affected: unspecified , < undefined (custom)

Date Public

2021-10-12 00:00

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.