Vulnerability-Lookup

GHSA-FC4C-4457-GW27

Vulnerability from github – Published: 2026-09-17 18:32 – Updated: 2026-09-17 18:32

Details

In the Linux kernel, the following vulnerability has been resolved:

bpf: Zero queue and stack outputs on lock failure

Queue and stack pop/peek helpers accept an uninitialized output buffer because the verifier expects the helper to initialize it. The empty-map error path clears the buffer, but a failed lock acquisition returns -EBUSY without writing it.

Clear the output before returning -EBUSY so BPF programs cannot observe uninitialized stack contents after a failed helper call.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-92520"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-17T17:17:54Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Zero queue and stack outputs on lock failure\n\nQueue and stack pop/peek helpers accept an uninitialized output buffer\nbecause the verifier expects the helper to initialize it. The empty-map\nerror path clears the buffer, but a failed lock acquisition returns\n-EBUSY without writing it.\n\nClear the output before returning -EBUSY so BPF programs cannot observe\nuninitialized stack contents after a failed helper call.",
  "id": "GHSA-fc4c-4457-gw27",
  "modified": "2026-09-17T18:32:07Z",
  "published": "2026-09-17T18:32:07Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-92520"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1534c4bff3aaca19c4c9a82f93e9b81f7c983de3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7ac6e1ae41a09f1dd4baeeff1d028ae49ee01232"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e2396b8a562073787e627a5f483f1bc5c452fa6a"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-92520 (GCVE-0-2026-92520)

Vulnerability from cvelistv5 – Published: 2026-09-17 16:10 – Updated: 2026-09-17 16:10

Title

bpf: Zero queue and stack outputs on lock failure

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Zero queue and stack outputs on lock failure Queue and stack pop/peek helpers accept an uninitialized output buffer because the verifier expects the helper to initialize it. The empty-map error path clears the buffer, but a failed lock acquisition returns -EBUSY without writing it. Clear the output before returning -EBUSY so BPF programs cannot observe uninitialized stack contents after a failed helper call.

Severity

No CVSS data available.

Assigner

Linux mitre root Scorecard

References

3 references

URL	Tags
https://git.kernel.org/stable/c/1534c4bff3aaca19c…
https://git.kernel.org/stable/c/e2396b8a562073787…
https://git.kernel.org/stable/c/7ac6e1ae41a09f1dd…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: a34a9f1a19afe9c60ca0ea61dfeee63a1c2baac8 , < 1534c4bff3aaca19c4c9a82f93e9b81f7c983de3 (git) Affected: a34a9f1a19afe9c60ca0ea61dfeee63a1c2baac8 , < e2396b8a562073787e627a5f483f1bc5c452fa6a (git) Affected: a34a9f1a19afe9c60ca0ea61dfeee63a1c2baac8 , < 7ac6e1ae41a09f1dd4baeeff1d028ae49ee01232 (git) Affected: 40e34ea01748e5b8afdd40a172868be1e1ab0ede (git) Affected: 388c9d3eefaea99828ee5000c693128a5b41ee7c (git) Affected: acabf5df49aa3a4f9c96200102d893351b511a88 (git) Affected: e388671635acf470f0986d874389148fd234620b (git) Affected: 232f0ba4d69263af5912e279fcc32fef2882b1dc (git) Affected: 5.4.258 , < 5.5 (semver) Affected: 5.10.198 , < 5.11 (semver) Affected: 5.15.134 , < 5.16 (semver) Affected: 6.1.56 , < 6.2 (semver) Affected: 6.5.6 , < 6.6 (semver)
Linux	Linux	Affected: 6.6 Unaffected: 0 , < 6.6 (semver) Unaffected: 6.18.52 , ≤ 6.18.* (semver) Unaffected: 7.2.6 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

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{
  "containers": {
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      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/queue_stack_maps.c"
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          "vendor": "Linux",
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            },
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              "versionType": "semver"
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          "vendor": "Linux",
          "versions": [
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              "version": "6.6"
            },
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              "status": "unaffected",
              "version": "0",
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              "status": "unaffected",
              "version": "6.18.52",
              "versionType": "semver"
            },
            {
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              "status": "unaffected",
              "version": "7.2.6",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
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        }
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      "providerMetadata": {
        "dateUpdated": "2026-09-17T16:10:27.447Z",
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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.

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.
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GHSA-FC4C-4457-GW27

CVE-2026-92520 (GCVE-0-2026-92520)

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