Vulnerability-Lookup

FKIE_CVE-2026-23432

Vulnerability from fkie_nvd - Published: 2026-04-03 16:16 - Updated: 2026-07-24 21:10

Severity

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

Summary

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix use-after-free in mshv_map_user_memory error path In the error path of mshv_map_user_memory(), calling vfree() directly on the region leaves the MMU notifier registered. When userspace later unmaps the memory, the notifier fires and accesses the freed region, causing a use-after-free and potential kernel panic. Replace vfree() with mshv_partition_put() to properly unregister the MMU notifier before freeing the region.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/34861bdc0c0196b6c2dd48f7454029407704ff6e	Patch
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6922db250422a0dfee34de322f86b7a73d713d33	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	6.19
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/hv/mshv_root_main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "34861bdc0c0196b6c2dd48f7454029407704ff6e",
              "status": "affected",
              "version": "b9a66cd5ccbb9fade15d0e427e19470d8ad35b75",
              "versionType": "git"
            },
            {
              "lessThan": "6922db250422a0dfee34de322f86b7a73d713d33",
              "status": "affected",
              "version": "b9a66cd5ccbb9fade15d0e427e19470d8ad35b75",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/hv/mshv_root_main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
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          "cpeMatch": [
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              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D70DEFFE-AC47-4F3A-A2B2-2D67AB4CF3C8",
              "versionEndExcluding": "6.19.10",
              "versionStartIncluding": "6.19.1",
              "vulnerable": true
            },
            {
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              "vulnerable": true
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            {
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              "vulnerable": true
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            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6",
              "vulnerable": true
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            {
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmshv: Fix use-after-free in mshv_map_user_memory error path\n\nIn the error path of mshv_map_user_memory(), calling vfree() directly on\nthe region leaves the MMU notifier registered. When userspace later unmaps\nthe memory, the notifier fires and accesses the freed region, causing a\nuse-after-free and potential kernel panic.\n\nReplace vfree() with mshv_partition_put() to properly unregister\nthe MMU notifier before freeing the region."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad:\n\nmshv: Correcci\u00f3n de uso despu\u00e9s de liberaci\u00f3n en la ruta de error de mshv_map_user_memory\n\nEn la ruta de error de mshv_map_user_memory(), llamar a vfree() directamente sobre la regi\u00f3n deja el notificador de MMU registrado. Cuando el espacio de usuario (userspace) desmapea la memoria m\u00e1s tarde, el notificador se activa y accede a la regi\u00f3n liberada, causando un uso despu\u00e9s de liberaci\u00f3n y un potencial p\u00e1nico del kernel.\n\nReemplace vfree() con mshv_partition_put() para anular correctamente el registro del notificador de MMU antes de liberar la regi\u00f3n."
    }
  ],
  "id": "CVE-2026-23432",
  "lastModified": "2026-07-24T21:10:00.143",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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        },
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        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      },
      {
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          "attackComplexity": "LOW",
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          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-04-03T16:16:24.637",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
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      "url": "https://git.kernel.org/stable/c/34861bdc0c0196b6c2dd48f7454029407704ff6e"
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    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2026-23432 (GCVE-0-2026-23432)

Vulnerability from cvelistv5 – Published: 2026-04-03 15:15 – Updated: 2026-08-05 12:21

Title

mshv: Fix use-after-free in mshv_map_user_memory error path

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/34861bdc0c0196b6c…
https://git.kernel.org/stable/c/6922db250422a0dfe…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: b9a66cd5ccbb9fade15d0e427e19470d8ad35b75 , < 34861bdc0c0196b6c2dd48f7454029407704ff6e (git) Affected: b9a66cd5ccbb9fade15d0e427e19470d8ad35b75 , < 6922db250422a0dfee34de322f86b7a73d713d33 (git)
Linux	Linux	Affected: 6.19 Unaffected: 0 , < 6.19 (semver) Unaffected: 6.19.10 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/hv/mshv_root_main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "34861bdc0c0196b6c2dd48f7454029407704ff6e",
              "status": "affected",
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              "versionType": "git"
            },
            {
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              "status": "affected",
              "version": "b9a66cd5ccbb9fade15d0e427e19470d8ad35b75",
              "versionType": "git"
            }
          ]
        },
        {
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          "product": "Linux",
          "programFiles": [
            "drivers/hv/mshv_root_main.c"
          ],
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          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
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              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "vulnerable": true
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        }
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      "metrics": [
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          "scenarios": [
            {
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              "value": "AV:L - The vulnerable path is reached through local `/dev/mshv` and partition-file ioctls, specifically `MSHV_SET_GUEST_MEMORY`, not via network or adjacent protocols.\nAC:L - The attacker controls the memory-region parameters and can subsequently unmap the userspace range to fire the stale MMU notifier. No attacker-uncontrolled race or special victim state is required.\nPR:L - The attacker needs local access to the mshv device or an already-created partition fd, but the vulnerable ioctl itself has no `capable()` check. In a reasonable VMM deployment where that fd/device is granted to a service process, this is Low rather than High.\nUI:N - After obtaining the local mshv interface, the attacker can issue the ioctl and unmap memory without requiring any separate user action.\nS:U - The bug corrupts kernel memory through a kernel driver interface and impacts the same kernel security authority. This is not a guest-to-host escape path from inside a VM.\nC:H - This is a use-after-free of a registered MMU interval notifier embedded in `struct mshv_mem_region`. Reuse of the freed vmalloc object can plausibly expose kernel memory or support read primitives.\nI:H - The stale notifier callback dereferences and writes through fields of freed attacker-reclaimable kernel memory, including notifier sequence and region state. As a kernel UAF, it is plausibly exploitable for memory corruption or control-flow impact.\nA:H - The upstream fix explicitly notes that later userspace unmapping can fire the notifier on freed memory and cause a kernel panic. A local attacker can trigger this repeatedly for host denial of service."
            }
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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

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FKIE_CVE-2026-23432

CVE-2026-23432 (GCVE-0-2026-23432)

Tags

Sightings

Nomenclature

Related by attack behaviour