CVE-2026-53321

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: io_uring/napi: cap busy_poll_to 10 msec Currently there's no cap on the maximum amount of time that napi is allowed to poll if no events are found, which can lead to kernel complaints on a task being stuck as there's no conditional rescheduling done within that loop. Just cap it to 10 msec in total, that's already way above any kind of sane value that will reap any benefits, yet low enough that it's nowhere near being able to trigger preemption complaints.

Severity

MEDIUM

CVSS score

5.5 (v3.1)

Vulnerability status

Modified

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-06-26 20:17:25.460000

Last modified

2026-10-21 13:19:14.910000

View original CVE JSON

{
  "id": "CVE-2026-53321",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-06-26T20:17:25.460",
  "lastModified": "2026-10-21T13:19:14.910",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/napi: cap busy_poll_to 10 msec\n\nCurrently there's no cap on the maximum amount of time that napi is\nallowed to poll if no events are found, which can lead to kernel\ncomplaints on a task being stuck as there's no conditional rescheduling\ndone within that loop.\n\nJust cap it to 10 msec in total, that's already way above any kind of\nsane value that will reap any benefits, yet low enough that it's\nnowhere near being able to trigger preemption complaints."
    }
  ],
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      "affectedData": [
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          "programFiles": [
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              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
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    }
  ],
  "metrics": {
    "cvssMetricV31": [
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        "type": "Primary",
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          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6
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  "weaknesses": [
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      "source": "[email protected]",
      "type": "Primary",
      "description": [
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          "lang": "en",
          "value": "NVD-CWE-noinfo"
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  "configurations": [
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