FKIE_CVE-2026-98164

Vulnerability from fkie_nvd - Published: 2026-09-29 13:17 - Updated: 2026-09-30 14:10
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Check write tracking in all address spaces kvm_gfn_is_write_tracked() checks only the supplied memslot, but page tracking is per-address-space and shadow pages are shared across all address spaces. With SMM, a GFN can therefore be write-tracked in one address space and appear untracked through the other. Check the supplied slot first, then the slot for the other address space. This ensures all callers honor write tracking regardless of the active address space. In particular, it prevents mmu_try_to_unsync_pages() from marking an upper-level shadow page unsync and eventually triggering the BUG in pte_list_remove(). [invert direction of the conditional. - Paolo]
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/09aa68552d2542cc6c23edd1568ac265dc5d886f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0f38453cdb2e17566ccb7c0f3dabd5bd21caca26
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/429b6f43b4d8c98988fdca99e02dc156134e3d77
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c0a9bd5fca0b5f2dea32b0fc31350e71e8648112
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d8636c8f9f95d0fd1e2f6f1cad0d5757aa6f212a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ec8fcaf354c1cbb36755d48e9f5a00c9591349e5
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/mmu/page_track.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "09aa68552d2542cc6c23edd1568ac265dc5d886f",
              "status": "affected",
              "version": "699023e239658e62da6f42f47d31b54788521ec1",
              "versionType": "git"
            },
            {
              "lessThan": "429b6f43b4d8c98988fdca99e02dc156134e3d77",
              "status": "affected",
              "version": "699023e239658e62da6f42f47d31b54788521ec1",
              "versionType": "git"
            },
            {
              "lessThan": "d8636c8f9f95d0fd1e2f6f1cad0d5757aa6f212a",
              "status": "affected",
              "version": "699023e239658e62da6f42f47d31b54788521ec1",
              "versionType": "git"
            },
            {
              "lessThan": "c0a9bd5fca0b5f2dea32b0fc31350e71e8648112",
              "status": "affected",
              "version": "699023e239658e62da6f42f47d31b54788521ec1",
              "versionType": "git"
            },
            {
              "lessThan": "ec8fcaf354c1cbb36755d48e9f5a00c9591349e5",
              "status": "affected",
              "version": "699023e239658e62da6f42f47d31b54788521ec1",
              "versionType": "git"
            },
            {
              "lessThan": "0f38453cdb2e17566ccb7c0f3dabd5bd21caca26",
              "status": "affected",
              "version": "699023e239658e62da6f42f47d31b54788521ec1",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/mmu/page_track.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.2"
            },
            {
              "lessThan": "4.2",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.187",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.156",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.108",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.49",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86/mmu: Check write tracking in all address spaces\n\nkvm_gfn_is_write_tracked() checks only the supplied memslot, but page\ntracking is per-address-space and shadow pages are shared across all\naddress spaces.  With SMM, a GFN can therefore be write-tracked in one\naddress space and appear untracked through the other.\n\nCheck the supplied slot first, then the slot for the other address space.\nThis ensures all callers honor write tracking regardless of the active\naddress space.  In particular, it prevents mmu_try_to_unsync_pages() from\nmarking an upper-level shadow page unsync and eventually triggering the\nBUG in pte_list_remove().\n\n[invert direction of the conditional. - Paolo]"
    }
  ],
  "id": "CVE-2026-98164",
  "lastModified": "2026-09-30T14:10:59.253",
  "metrics": {},
  "published": "2026-09-29T13:17:53.710",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/09aa68552d2542cc6c23edd1568ac265dc5d886f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0f38453cdb2e17566ccb7c0f3dabd5bd21caca26"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/429b6f43b4d8c98988fdca99e02dc156134e3d77"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c0a9bd5fca0b5f2dea32b0fc31350e71e8648112"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d8636c8f9f95d0fd1e2f6f1cad0d5757aa6f212a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ec8fcaf354c1cbb36755d48e9f5a00c9591349e5"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}



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