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GHSA-8M43-M8XF-JM3H

Vulnerability from github – Published: 2026-08-27 06:31 – Updated: 2026-08-27 06:31

Details

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

drm/shmem_helper: Check VMA boundaries for PMD mappings

In the ->huge_fault handler do not install a PMD huge page mapping if the huge page exceeds the boundaries of the VMA.

All other ->huge_fault handlers have similar checks and the resulting mapping will trigger a VM_BUG_ON_VMA() if it ever reaches copy_pmd_range().

Severity

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-80582"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-26T15:17:14Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/shmem_helper: Check VMA boundaries for PMD mappings\n\nIn the -\u003ehuge_fault handler do not install a PMD huge page\nmapping if the huge page exceeds the boundaries of the VMA.\n\nAll other -\u003ehuge_fault handlers have similar checks and the\nresulting mapping will trigger a VM_BUG_ON_VMA() if it ever\nreaches copy_pmd_range().",
  "id": "GHSA-8m43-m8xf-jm3h",
  "modified": "2026-08-27T06:31:33Z",
  "published": "2026-08-27T06:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80582"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/12803e89a1e593fd1e784dfe7453f5e392ccaff2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/617bbd08714857c1613d7c550d43a9092ec0fb97"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-80582 (GCVE-0-2026-80582)

Vulnerability from cvelistv5 – Published: 2026-08-26 14:37 – Updated: 2026-08-27 05:02

Title

drm/shmem_helper: Check VMA boundaries for PMD mappings

Summary

In the Linux kernel, the following vulnerability has been resolved: drm/shmem_helper: Check VMA boundaries for PMD mappings In the ->huge_fault handler do not install a PMD huge page mapping if the huge page exceeds the boundaries of the VMA. All other ->huge_fault handlers have similar checks and the resulting mapping will trigger a VM_BUG_ON_VMA() if it ever reaches copy_pmd_range().

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/12803e89a1e593fd1…
https://git.kernel.org/stable/c/617bbd08714857c16…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: fc3bbf34e643faa8678aabdc3810c60109f3435a , < 12803e89a1e593fd1e784dfe7453f5e392ccaff2 (git) Affected: fc3bbf34e643faa8678aabdc3810c60109f3435a , < 617bbd08714857c1613d7c550d43a9092ec0fb97 (git)
Linux	Linux	Affected: 7.0 Unaffected: 0 , < 7.0 (semver) Unaffected: 7.1.10 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/drm_gem_shmem_helper.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "12803e89a1e593fd1e784dfe7453f5e392ccaff2",
              "status": "affected",
              "version": "fc3bbf34e643faa8678aabdc3810c60109f3435a",
              "versionType": "git"
            },
            {
              "lessThan": "617bbd08714857c1613d7c550d43a9092ec0fb97",
              "status": "affected",
              "version": "fc3bbf34e643faa8678aabdc3810c60109f3435a",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/drm_gem_shmem_helper.c"
          ],
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          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.0"
            },
            {
              "lessThan": "7.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.10",
                  "versionStartIncluding": "7.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "7.0",
                  "vulnerable": true
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              "operator": "OR"
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/shmem_helper: Check VMA boundaries for PMD mappings\n\nIn the -\u003ehuge_fault handler do not install a PMD huge page\nmapping if the huge page exceeds the boundaries of the VMA.\n\nAll other -\u003ehuge_fault handlers have similar checks and the\nresulting mapping will trigger a VM_BUG_ON_VMA() if it ever\nreaches copy_pmd_range()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - Reachable via local mmap/page-fault on DRM GEM shmem buffers (drm_gem_mmap -\u003e drm_gem_shmem_any_fault -\u003e try_insert_pfn PMD path), used by virtio-gpu, panfrost, lima, v3d, panthor, and other GPU/accelerator drivers on phones, VMs, and desktops.\nAC:L - An attacker controls GEM buffer size, mmap length, fault addresses, and follow-on fork/mprotect; no race or rare layout is required beyond creating a non-PMD-aligned mapping near a VMA end so a 2MB PMD install overruns the VMA.\nPR:L - Only standard local GPU access is needed (open /dev/dri/renderD* or card*, DRM GEM create/mmap ioctls); no CAP_SYS_ADMIN or init-namespace root, matching unprivileged desktop render-group users, Android GPU apps, and cloud/VM GPU workloads.\nUI:N - Exploitation is fully attacker-driven through their own DRM client (create buffer, mmap, touch pages, fork); no separate victim action such as opening a file or mounting a filesystem is required.\nS:U - Impact stays within the kernel/GPU process security boundary (local memory corruption and kernel panic); it does not cross VM/host, IOMMU, or sandbox authority boundaries.\nC:H - Without the VMA boundary check, a 2MB PMD PFNMAP can cover virtual/physical pages beyond the GEM object and VMA, creating out-of-bounds read primitives from adjacent mapped memory before copy_pmd_range() trips VM_BUG_ON_VMA().\nI:H - The same oversized PMD mapping installs writable PFNMAP entries beyond the allocated buffer, enabling out-of-bounds writes and corrupt page tables exploitable for control-flow or data tampering, not merely a clean fault.\nA:H - The invalid PMD eventually hits VM_BUG_ON_VMA() in copy_pmd_range() or __split_huge_pmd() (e.g., fork of the mapping), producing a kernel BUG/oops and panic as demonstrated in related drm/shmem_helper THP testing."
            }
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      "providerMetadata": {
        "dateUpdated": "2026-08-27T05:02:02.758Z",
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          "url": "https://git.kernel.org/stable/c/617bbd08714857c1613d7c550d43a9092ec0fb97"
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      "title": "drm/shmem_helper: Check VMA boundaries for PMD mappings",
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    "cveId": "CVE-2026-80582",
    "datePublished": "2026-08-26T14:37:39.113Z",
    "dateReserved": "2026-08-26T14:34:25.769Z",
    "dateUpdated": "2026-08-27T05:02:02.758Z",
    "state": "PUBLISHED"
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  "dataVersion": "5.2"
}

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.
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GHSA-8M43-M8XF-JM3H

CVE-2026-80582 (GCVE-0-2026-80582)

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