fkie_nvd - fkie_cve-2025-39816

FKIE_CVE-2025-39816

Vulnerability from fkie_nvd - Published: 2025-09-16 13:15 - Updated: 2025-12-02 19:04

Severity ?

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

Summary

In the Linux kernel, the following vulnerability has been resolved: io_uring/kbuf: always use READ_ONCE() to read ring provided buffer lengths Since the buffers are mapped from userspace, it is prudent to use READ_ONCE() to read the value into a local variable, and use that for any other actions taken. Having a stable read of the buffer length avoids worrying about it changing after checking, or being read multiple times. Similarly, the buffer may well change in between it being picked and being committed. Ensure the looping for incremental ring buffer commit stops if it hits a zero sized buffer, as no further progress can be made at that point.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/390a61d284e1ced088d43928dfcf6f86fffdd780	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/695673eb5711ee5eb1769481cf1503714716a7d1	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/98b6fa62c84f2e129161e976a5b9b3cb4ccd117b	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17

JSON

To clipboard

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "91ABE7C0-8B2A-4A71-9635-E30621CFB875",
              "versionEndExcluding": "6.12.49",
              "versionStartIncluding": "6.12",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "EB781080-7001-4FA1-B388-517FFEFBC73E",
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            },
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  "cveTags": [],
  "descriptions": [
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      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/kbuf: always use READ_ONCE() to read ring provided buffer lengths\n\nSince the buffers are mapped from userspace, it is prudent to use\nREAD_ONCE() to read the value into a local variable, and use that for\nany other actions taken. Having a stable read of the buffer length\navoids worrying about it changing after checking, or being read multiple\ntimes.\n\nSimilarly, the buffer may well change in between it being picked and\nbeing committed. Ensure the looping for incremental ring buffer commit\nstops if it hits a zero sized buffer, as no further progress can be made\nat that point."
    }
  ],
  "id": "CVE-2025-39816",
  "lastModified": "2025-12-02T19:04:00.170",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
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    ]
  },
  "published": "2025-09-16T13:15:56.790",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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    },
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    },
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  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2025-39816 (GCVE-0-2025-39816)

Vulnerability from cvelistv5 – Published: 2025-09-16 13:00 – Updated: 2025-09-29 06:00

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/695673eb5711ee5eb…
	https://git.kernel.org/stable/c/390a61d284e1ced08…
	https://git.kernel.org/stable/c/98b6fa62c84f2e129…

Impacted products

Vendor

Product

Version

Linux

Affected: ae98dbf43d755b4e111fcd086e53939bef3e9a1a , < 695673eb5711ee5eb1769481cf1503714716a7d1 (git)
Affected: ae98dbf43d755b4e111fcd086e53939bef3e9a1a , < 390a61d284e1ced088d43928dfcf6f86fffdd780 (git)
Affected: ae98dbf43d755b4e111fcd086e53939bef3e9a1a , < 98b6fa62c84f2e129161e976a5b9b3cb4ccd117b (git)

Linux

Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.49 , ≤ 6.12.* (semver)
Unaffected: 6.16.5 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "io_uring/kbuf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
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              "status": "affected",
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              "versionType": "git"
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              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "98b6fa62c84f2e129161e976a5b9b3cb4ccd117b",
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              "versionType": "git"
            }
          ]
        },
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          "product": "Linux",
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            {
              "status": "affected",
              "version": "6.12"
            },
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              "lessThan": "6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.49",
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            },
            {
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              "version": "6.16.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.17",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
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        }
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}

Sightings

Author	Source	Type	Date

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.

Action not permitted

FKIE_CVE-2025-39816

CVE-2025-39816 (GCVE-0-2025-39816)

Tags

Sightings

Nomenclature