CVE-2026-72174

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-72174", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.910Z", "datePublished": "2026-08-15T05:53:39.276Z", "dateUpdated": "2026-08-17T05:09:36.416Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:09:36.416Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()\n\nA PAGEMAP_SCAN ioctl requesting PM_SCAN_WP_MATCHING on a hugetlb VMA hangs\nthe calling thread, unkillably, as soon as the scan reaches an unpopulated\npart of the range:\n\n do_pagemap_scan()\n walk_page_range()\n walk_hugetlb_range()\n hugetlb_vma_lock_read() # take the vma lock for read ...\n pagemap_scan_pte_hole() # ... ->pte_hole() for a hole\n uffd_wp_range()\n change_protection()\n hugetlb_change_protection()\n hugetlb_vma_lock_write() # ... and block taking it for write\n\nwalk_hugetlb_range() holds the hugetlb vma lock for read across the whole\nwalk. A present entry goes to ->hugetlb_entry(); an unpopulated one goes\nto ->pte_hole(), i.e. pagemap_scan_pte_hole(). To write-protect the hole\nthat handler calls uffd_wp_range(), which on a hugetlb VMA reaches\nhugetlb_change_protection() and takes the same vma lock for write. The\nthread then blocks in down_write() waiting for the read lock it is itself\nholding.\n\nThe populated path avoids this: pagemap_scan_hugetlb_entry()\nwrite-protects the entry inline under the page-table lock and never enters\nhugetlb_change_protection().\n\nDo the same for holes. Fault in the page table and install the uffd-wp\nmarker directly with make_uffd_wp_huge_pte() under the page-table lock,\nrather than routing through uffd_wp_range(). That is the same sequence\nhugetlb_change_protection() runs for an unpopulated entry, minus the vma\nwrite lock -- which is safe to skip because PMD sharing is disabled on\nuffd-wp VMAs (hugetlb_unshare_all_pmds() runs at registration), leaving\nnothing for that lock to serialise against."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/proc/task_mmu.c"], "versions": [{"version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "lessThan": "a6ac03652d9edc30c2912037ac83beb42cc67f8e", "status": "affected", "versionType": "git"}, {"version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "lessThan": "43b987ed35be9be21a303d1036d4241fec9943df", "status": "affected", "versionType": "git"}, {"version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "lessThan": "18b8a9700610299819d21fd0ea85d24726d17f65", "status": "affected", "versionType": "git"}, {"version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "lessThan": "e92d92bbafb264dc0518d52b846a3c07ed8d523f", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/proc/task_mmu.c"], "versions": [{"version": "6.7", "status": "affected"}, {"version": "0", "lessThan": "6.7", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.97"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.18.40"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a6ac03652d9edc30c2912037ac83beb42cc67f8e"}, {"url": "https://git.kernel.org/stable/c/43b987ed35be9be21a303d1036d4241fec9943df"}, {"url": "https://git.kernel.org/stable/c/18b8a9700610299819d21fd0ea85d24726d17f65"}, {"url": "https://git.kernel.org/stable/c/e92d92bbafb264dc0518d52b846a3c07ed8d523f"}], "title": "fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/proc/task_mmu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a6ac03652d9edc30c2912037ac83beb42cc67f8e", "status": "affected", "version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "versionType": "git"}, {"lessThan": "43b987ed35be9be21a303d1036d4241fec9943df", "status": "affected", "version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "versionType": "git"}, {"lessThan": "18b8a9700610299819d21fd0ea85d24726d17f65", "status": "affected", "version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "versionType": "git"}, {"lessThan": "e92d92bbafb264dc0518d52b846a3c07ed8d523f", "status": "affected", "version": "52526ca7fdb905a768a93f8faa418e9b988fc34b", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/proc/task_mmu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.7"}, {"lessThan": "6.7", "status": "unaffected", "version": "0", "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"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()\n\nA PAGEMAP_SCAN ioctl requesting PM_SCAN_WP_MATCHING on a hugetlb VMA hangs\nthe calling thread, unkillably, as soon as the scan reaches an unpopulated\npart of the range:\n\n do_pagemap_scan()\n walk_page_range()\n walk_hugetlb_range()\n hugetlb_vma_lock_read() # take the vma lock for read ...\n pagemap_scan_pte_hole() # ... ->pte_hole() for a hole\n uffd_wp_range()\n change_protection()\n hugetlb_change_protection()\n hugetlb_vma_lock_write() # ... and block taking it for write\n\nwalk_hugetlb_range() holds the hugetlb vma lock for read across the whole\nwalk. A present entry goes to ->hugetlb_entry(); an unpopulated one goes\nto ->pte_hole(), i.e. pagemap_scan_pte_hole(). To write-protect the hole\nthat handler calls uffd_wp_range(), which on a hugetlb VMA reaches\nhugetlb_change_protection() and takes the same vma lock for write. The\nthread then blocks in down_write() waiting for the read lock it is itself\nholding.\n\nThe populated path avoids this: pagemap_scan_hugetlb_entry()\nwrite-protects the entry inline under the page-table lock and never enters\nhugetlb_change_protection().\n\nDo the same for holes. Fault in the page table and install the uffd-wp\nmarker directly with make_uffd_wp_huge_pte() under the page-table lock,\nrather than routing through uffd_wp_range(). That is the same sequence\nhugetlb_change_protection() runs for an unpopulated entry, minus the vma\nwrite lock -- which is safe to skip because PMD sharing is disabled on\nuffd-wp VMAs (hugetlb_unshare_all_pmds() runs at registration), leaving\nnothing for that lock to serialise against."}], "id": "CVE-2026-72174", "lastModified": "2026-08-17T06:18:17.883", "metrics": {}, "published": "2026-08-15T06:21:35.567", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/18b8a9700610299819d21fd0ea85d24726d17f65"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/43b987ed35be9be21a303d1036d4241fec9943df"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a6ac03652d9edc30c2912037ac83beb42cc67f8e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e92d92bbafb264dc0518d52b846a3c07ed8d523f"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()", "id": "2516457", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2516457"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-833", "details": ["A flaw was found in the Linux kernel. A local attacker could trigger a self-deadlock condition within the huge pages (hugetlb) memory management subsystem. This occurs when a specific memory scan operation attempts to acquire a write lock while the same process already holds a read lock, causing the affected thread to hang indefinitely. This vulnerability leads to a denial of service, making the system unresponsive."], "name": "CVE-2026-72174", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-08-15T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-72174\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-72174\nhttps://lore.kernel.org/linux-cve-announce/2026081538-CVE-2026-72174-4980@gregkh/T"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[52526ca7fdb905a768a93f8faa418e9b988fc34b,a6ac03652d9edc30c2912037ac83beb42cc67f8e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[52526ca7fdb905a768a93f8faa418e9b988fc34b,43b987ed35be9be21a303d1036d4241fec9943df)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[52526ca7fdb905a768a93f8faa418e9b988fc34b,18b8a9700610299819d21fd0ea85d24726d17f65)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[52526ca7fdb905a768a93f8faa418e9b988fc34b,e92d92bbafb264dc0518d52b846a3c07ed8d523f)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.7"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.7)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.97,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.40,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.5,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-15T20:30:14.231066+00:00", "updated": "2026-08-22T09:00:10.817922+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-833"]}