Vulnerability-Lookup

CVE-2026-43045 (GCVE-0-2026-43045)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:15 – Updated: 2026-05-02 06:14

Title

mshv: Fix error handling in mshv_region_pin

Summary

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix error handling in mshv_region_pin The current error handling has two issues: First, pin_user_pages_fast() can return a short pin count (less than requested but greater than zero) when it cannot pin all requested pages. This is treated as success, leading to partially pinned regions being used, which causes memory corruption. Second, when an error occurs mid-loop, already pinned pages from the current batch are not properly accounted for before calling mshv_region_invalidate_pages(), causing a page reference leak. Treat short pins as errors and fix partial batch accounting before cleanup.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/a7d149152bc5a9119…
	https://git.kernel.org/stable/c/c0e296f257671ba10…

Impacted products

Vendor

Product

Version

Linux

Affected: 621191d709b14882270dfd8ea5d7d6cdfebe2c35 , < a7d149152bc5a9119854331c57be35ad31fdf5cc (git)
Affected: 621191d709b14882270dfd8ea5d7d6cdfebe2c35 , < c0e296f257671ba10249630fe58026f29e4804d9 (git)

Linux

Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
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      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/hv/mshv_regions.c"
          ],
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          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "c0e296f257671ba10249630fe58026f29e4804d9",
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              "versionType": "git"
            }
          ]
        },
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              "version": "0",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "6.19.12",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
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                  "vulnerable": true
                },
                {
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                  "versionEndExcluding": "7.0",
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmshv: Fix error handling in mshv_region_pin\n\nThe current error handling has two issues:\n\nFirst, pin_user_pages_fast() can return a short pin count (less than\nrequested but greater than zero) when it cannot pin all requested pages.\nThis is treated as success, leading to partially pinned regions being\nused, which causes memory corruption.\n\nSecond, when an error occurs mid-loop, already pinned pages from the\ncurrent batch are not properly accounted for before calling\nmshv_region_invalidate_pages(), causing a page reference leak.\n\nTreat short pins as errors and fix partial batch accounting before\ncleanup."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-02T06:14:30.662Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/a7d149152bc5a9119854331c57be35ad31fdf5cc"
        },
        {
          "url": "https://git.kernel.org/stable/c/c0e296f257671ba10249630fe58026f29e4804d9"
        }
      ],
      "title": "mshv: Fix error handling in mshv_region_pin",
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      }
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43045",
    "datePublished": "2026-05-01T14:15:40.976Z",
    "dateReserved": "2026-05-01T14:12:55.979Z",
    "dateUpdated": "2026-05-02T06:14:30.662Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
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    "epss": {
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      "date": "2026-05-04",
      "epss": "0.00018",
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  }
}

MSRC_CVE-2026-43045

Vulnerability from csaf_microsoft - Published: 2026-05-02 00:00 - Updated: 2026-05-02 01:03

Summary

mshv: Fix error handling in mshv_region_pin

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

CVE-2026-43045

References

URL

Category

	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self
	https://support.microsoft.com/lifecycle	external
	https://www.first.org/cvss	external
	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self

JSON

To clipboard

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-43045 mshv: Fix error handling in mshv_region_pin - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-43045.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "mshv: Fix error handling in mshv_region_pin",
    "tracking": {
      "current_release_date": "2026-05-02T01:03:37.000Z",
      "generator": {
        "date": "2026-05-03T07:02:17.471Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-43045",
      "initial_release_date": "2026-05-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-05-02T01:03:37.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
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  "product_tree": {
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            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
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            "category": "product_name",
            "name": "Azure Linux"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-43045",
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
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      "references": [
        {
          "category": "self",
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      ],
      "title": "mshv: Fix error handling in mshv_region_pin"
    }
  ]
}

FKIE_CVE-2026-43045

Vulnerability from fkie_nvd - Published: 2026-05-01 15:16 - Updated: 2026-05-01 15:24

Severity ?

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a7d149152bc5a9119854331c57be35ad31fdf5cc
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/c0e296f257671ba10249630fe58026f29e4804d9

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmshv: Fix error handling in mshv_region_pin\n\nThe current error handling has two issues:\n\nFirst, pin_user_pages_fast() can return a short pin count (less than\nrequested but greater than zero) when it cannot pin all requested pages.\nThis is treated as success, leading to partially pinned regions being\nused, which causes memory corruption.\n\nSecond, when an error occurs mid-loop, already pinned pages from the\ncurrent batch are not properly accounted for before calling\nmshv_region_invalidate_pages(), causing a page reference leak.\n\nTreat short pins as errors and fix partial batch accounting before\ncleanup."
    }
  ],
  "id": "CVE-2026-43045",
  "lastModified": "2026-05-01T15:24:14.893",
  "metrics": {},
  "published": "2026-05-01T15:16:50.817",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a7d149152bc5a9119854331c57be35ad31fdf5cc"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c0e296f257671ba10249630fe58026f29e4804d9"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

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.

Action not permitted

CVE-2026-43045 (GCVE-0-2026-43045)

MSRC_CVE-2026-43045

FKIE_CVE-2026-43045

Tags

Sightings

Nomenclature