{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/loongarch/include/asm/pgtable.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "76f88650763a35cbf1384c65d66d096fa31cc58d",
              "status": "affected",
              "version": "09cfefb7fa70c3af011b0db0a513fd80b2f18abc",
              "versionType": "git"
            },
            {
              "lessThan": "e8a916579e427af32f2de8213dfa23c5df6e6664",
              "status": "affected",
              "version": "09cfefb7fa70c3af011b0db0a513fd80b2f18abc",
              "versionType": "git"
            },
            {
              "lessThan": "39bb21a4bff0d70058bf752d7b5aa2e2ccc864a9",
              "status": "affected",
              "version": "09cfefb7fa70c3af011b0db0a513fd80b2f18abc",
              "versionType": "git"
            },
            {
              "lessThan": "a65f49b6f7ece756394f8f0e85570020e7fd0e35",
              "status": "affected",
              "version": "09cfefb7fa70c3af011b0db0a513fd80b2f18abc",
              "versionType": "git"
            },
            {
              "lessThan": "e483da960892c41fa7f0cf0d2fc2410d65a483d6",
              "status": "affected",
              "version": "09cfefb7fa70c3af011b0db0a513fd80b2f18abc",
              "versionType": "git"
            },
            {
              "lessThan": "018e9828eb523c638fa3d9bdf0fd4956b74555b2",
              "status": "affected",
              "version": "09cfefb7fa70c3af011b0db0a513fd80b2f18abc",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/loongarch/include/asm/pgtable.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.19"
            },
            {
              "lessThan": "5.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "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": "6.1.178",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nLoongArch: Fix missing dirty page tracking in {pte,pmd}_wrprotect()\n\nWhen hardware page table walker (PTW) is enabled on LoongArch, the CPU\nmay set _PAGE_DIRTY directly in the page table entry during a write TLB\nmiss, without going through the software TLB store handler. The software\nTLB store handler (tlbex.S:254) sets both _PAGE_DIRTY and_PAGE_MODIFIED\ntogether:\n\n    ori t0, t0, (_PAGE_VALID | _PAGE_DIRTY | _PAGE_MODIFIED)\n\nSince hardware PTW only sets _PAGE_DIRTY, the software-only bit, i.e.\n_PAGE_MODIFIED is left unchanged. This creates a window where a PTE has\n_PAGE_DIRTY set (hardware knows the page is dirty) but _PAGE_MODIFIED\nclear (software is unaware).\n\nWhen fork()/clone() triggers copy-on-write, __copy_present_ptes() calls\npte_wrprotect(), which unconditionally clears both the _PAGE_WRITE and\n_PAGE_DIRTY bits:\n\n    pte_val(pte) \u0026= ~(_PAGE_WRITE | _PAGE_DIRTY);\n\nSince _PAGE_MODIFIED was never set, the dirtiness information is lost\ncompletely. Subsequently, when memory pressure triggers page reclaim,\npage_mkclean() / try_to_unmap() sees the page as clean (i.e. pte_dirty()\nreturns false) and the page may be freed without writeback, causing data\ncorruption.\n\nFix this by propagating the _PAGE_DIRTY bit to the _PAGE_MODIFIED bit in\nboth pte_wrprotect() and pmd_wrprotect() before clearing writeable bits:\n\n    if (pte_val(pte) \u0026 _PAGE_DIRTY)\n        pte_val(pte) |= _PAGE_MODIFIED;\n\nThe pmd_wrprotect() fix handles the CONFIG_TRANSPARENT_HUGEPAGE case,\nwhere pmd entries need the same treatment.\n\nThis ensures the software dirty tracking bit (checked by pte_dirty() and\npmd_dirty(), which read both the _PAGE_DIRTY and _PAGE_MODIFIED bits) is\npreserved across fork COW write-protection.\n\nThe issue was found by the LTP madvise09 test case, which exercises page\nreclaim after \"madvise(MADV_FREE), write and fork\" operation sequence on\nprivate anonymous mappings."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is triggered via local syscalls (mmap/madvise/write/fork or clone) through dup_mmap()-\u003ecopy_page_range()-\u003epte_wrprotect() on LoongArch; it is not reachable from network-facing kernel services.\nAC:L - An unprivileged attacker can reliably reproduce the LTP madvise09 sequence (MADV_FREE, write, fork, then force reclaim) on LoongArch CPUs with hardware PTW; no races or victim-specific state beyond attacker-controlled memory pressure are required.\nPR:L - No special capabilities are needed; any local user can create private anonymous or file-backed COW mappings, write them, fork, and drive page reclaim using standard unprivileged syscalls.\nUI:N - Exploitation requires no action from another user; the attacker controls the full trigger sequence in their own process or in a service worker they operate.\nS:U - Impact is confined to kernel memory-management integrity on the host; it does not constitute a VM escape, sandbox escape, or IOMMU/DMA boundary bypass.\nC:H - Incorrectly treating hardware-dirty pages as clean during reclaim can free page frames without writeback or swap, leaving prior contents in the buddy allocator for reuse by other mappings and enabling cross-process information disclosure.\nI:H - Lost dirty tracking causes silent discard of modified pages during reclaim without writeback, corrupting private anonymous data and file-backed COW mappings when dirty pages are freed or swapped incorrectly.\nA:N - The defect causes silent data corruption rather than kernel oops, panic, or hang; the system remains operational even when pages are incorrectly reclaimed."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:39:42.678Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/76f88650763a35cbf1384c65d66d096fa31cc58d"
        },
        {
          "url": "https://git.kernel.org/stable/c/e8a916579e427af32f2de8213dfa23c5df6e6664"
        },
        {
          "url": "https://git.kernel.org/stable/c/39bb21a4bff0d70058bf752d7b5aa2e2ccc864a9"
        },
        {
          "url": "https://git.kernel.org/stable/c/a65f49b6f7ece756394f8f0e85570020e7fd0e35"
        },
        {
          "url": "https://git.kernel.org/stable/c/e483da960892c41fa7f0cf0d2fc2410d65a483d6"
        },
        {
          "url": "https://git.kernel.org/stable/c/018e9828eb523c638fa3d9bdf0fd4956b74555b2"
        }
      ],
      "title": "LoongArch: Fix missing dirty page tracking in {pte,pmd}_wrprotect()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72043",
    "datePublished": "2026-08-15T05:52:02.505Z",
    "dateReserved": "2026-08-09T03:40:39.902Z",
    "dateUpdated": "2026-08-17T05:39:42.678Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}