{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-80685", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.784Z", "datePublished": "2026-08-28T06:52:51.305Z", "dateUpdated": "2026-08-29T06:22:12.733Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-29T06:22:12.733Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/util: don't read __page_2 for order-1 folios in snapshot_page()\n\nsnapshot_page() currently reads __page_2 after checking nr_pages > 1, but\nit should only do so when nr_pages > 2.\n\nIf an order-1 folio is allocated at the end of a vmemmap section,\n__page_2 will not exist and reading it will cause a fault.\n\nDuring DLPAR memory remove on a 22 TB ppc64le LPAR, snapshot_page() oopsed\non the page isolation path while reading an order-1 folio's __page_2 from\nan adjacent absent section (unmapped vmemmap).\n\nFix this to avoid reading memmap that doesn't exist (e.g., a vmemmap\nhole)."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - Reachable via local read(2) on /proc/kpageflags or /proc/kpagecount (kpage_read\u2192stable_page_flags/get_kpage_count\u2192snapshot_page); the reported production crash also occurs on the memory-hotplug page-isolation dump_page path during offline_pages/DLPAR, with no network or physical-bus entry point.\nAC:L - A container/user-namespace root can sequentially scan PFNs via /proc/kpageflags until snapshot_page hits an order-1 folio at a vmemmap section boundary; on large SPARSEMEM_VMEMMAP systems such folios exist naturally (22 TB ppc64le LPAR oops) without races or attacker-uncontrollable timing.\nPR:L - /proc/kpage* is mode 0400 (root-only); exploitation needs only namespace/container root or CAP_SYS_ADMIN in a user namespace to read host proc on typical Docker/K8s/cloud nodes\u2014not init-namespace root; the DLPAR offline path needs admin but is not the lowest-privilege vector.\nUI:N - The attacker performs their own /proc/kpageflags reads or triggers kernel debug dumps; no separate victim action such as opening a file, mounting a filesystem, or approving a prompt is required beyond having local proc access.\nS:U - Impact is a kernel oops/panic within the host kernel security boundary; there is no VM escape, IOMMU bypass, or cross-authority resource access beyond crashing or destabilizing the shared kernel.\nC:H - snapshot_page() performs memcpy of a full struct page from foliop->__page_2 when only two pages are valid for order-1 folios, reading beyond allocated vmemmap into an unmapped hole; this out-of-bounds kernel read can expose adjacent mapped memmap bytes to the snapshot buffer on some layouts before faulting.\nI:N - The defect is a read past valid folio memmap that page-faults in kernel mode; memcpy only fills a local page_snapshot buffer and does not corrupt kernel objects, enable arbitrary writes, or provide a control-flow hijack primitive.\nA:H - Reading absent vmemmap for order-1 folios at section boundaries causes a supervisor page fault and kernel oops, as demonstrated during DLPAR memory remove on ppc64le; repeated /proc/kpageflags scanning can reliably panic or hang large-memory cloud/LPAR hosts."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/util.c"], "versions": [{"version": "31a31da8a6187f1e5448ec73222e01d7d3fed4aa", "lessThan": "9668ffe0e2a5e2399dce281620198a2e415871fc", "status": "affected", "versionType": "git"}, {"version": "31a31da8a6187f1e5448ec73222e01d7d3fed4aa", "lessThan": "c649324571206a30949765320b91ccdb4c1722dc", "status": "affected", "versionType": "git"}, {"version": "31a31da8a6187f1e5448ec73222e01d7d3fed4aa", "lessThan": "7441d6348c70738e9ed307510db171c7a9b3f4bf", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/util.c"], "versions": [{"version": "6.15", "status": "affected"}, {"version": "0", "lessThan": "6.15", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.44", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.8", "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": "6.15", "versionEndExcluding": "6.18.44"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "7.1.8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/9668ffe0e2a5e2399dce281620198a2e415871fc"}, {"url": "https://git.kernel.org/stable/c/c649324571206a30949765320b91ccdb4c1722dc"}, {"url": "https://git.kernel.org/stable/c/7441d6348c70738e9ed307510db171c7a9b3f4bf"}], "title": "mm/util: don't read __page_2 for order-1 folios in snapshot_page()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["mm/util.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "9668ffe0e2a5e2399dce281620198a2e415871fc", "status": "affected", "version": "31a31da8a6187f1e5448ec73222e01d7d3fed4aa", "versionType": "git"}, {"lessThan": "c649324571206a30949765320b91ccdb4c1722dc", "status": "affected", "version": "31a31da8a6187f1e5448ec73222e01d7d3fed4aa", "versionType": "git"}, {"lessThan": "7441d6348c70738e9ed307510db171c7a9b3f4bf", "status": "affected", "version": "31a31da8a6187f1e5448ec73222e01d7d3fed4aa", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["mm/util.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.15"}, {"lessThan": "6.15", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.44", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.8", "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\nmm/util: don't read __page_2 for order-1 folios in snapshot_page()\n\nsnapshot_page() currently reads __page_2 after checking nr_pages > 1, but\nit should only do so when nr_pages > 2.\n\nIf an order-1 folio is allocated at the end of a vmemmap section,\n__page_2 will not exist and reading it will cause a fault.\n\nDuring DLPAR memory remove on a 22 TB ppc64le LPAR, snapshot_page() oopsed\non the page isolation path while reading an order-1 folio's __page_2 from\nan adjacent absent section (unmapped vmemmap).\n\nFix this to avoid reading memmap that doesn't exist (e.g., a vmemmap\nhole)."}], "id": "CVE-2026-80685", "lastModified": "2026-08-29T07:16:51.120", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.2, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-08-28T08:16:53.963", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7441d6348c70738e9ed307510db171c7a9b3f4bf"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9668ffe0e2a5e2399dce281620198a2e415871fc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c649324571206a30949765320b91ccdb4c1722dc"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: mm/util: don't read __page_2 for order-1 folios in snapshot_page()", "id": "2525454", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2525454"}, "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-125", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nmm/util: don't read __page_2 for order-1 folios in snapshot_page()\nsnapshot_page() currently reads __page_2 after checking nr_pages > 1, but\nit should only do so when nr_pages > 2.\nIf an order-1 folio is allocated at the end of a vmemmap section,\n__page_2 will not exist and reading it will cause a fault.\nDuring DLPAR memory remove on a 22 TB ppc64le LPAR, snapshot_page() oopsed\non the page isolation path while reading an order-1 folio's __page_2 from\nan adjacent absent section (unmapped vmemmap).\nFix this to avoid reading memmap that doesn't exist (e.g., a vmemmap\nhole).", "A flaw was found in the Linux kernel's memory management subsystem. The `snapshot_page()` function attempts to read memory that may not exist when handling certain memory structures (order-1 folios) during specific memory operations, such as dynamic logical partitioning (DLPAR) memory removal. This out-of-bounds read can lead to a kernel fault (oops), resulting in a system crash and a Denial of Service (DoS)."], "name": "CVE-2026-80685", "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": "2026-08-28T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-80685\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-80685\nhttps://lore.kernel.org/linux-cve-announce/2026082802-CVE-2026-80685-a81f@gregkh/T"], "threat_severity": "Low"}