{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-80682", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.784Z", "datePublished": "2026-08-28T06:52:49.498Z", "dateUpdated": "2026-08-29T06:22:09.064Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-29T06:22:09.064Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nriscv/mm: use physical alignment for vmemmap_start_pfn\n\nRISC-V computes vmemmap_start_pfn by rounding phys_ram_base down to\nVMEMMAP_ADDR_ALIGN. That alignment must therefore be expressed in the\nphysical-address domain.\n\nCommit 476849b0fba4 (\"riscv/mm: align vmemmap to maximal folio size\")\nattempted to account for the maximal folio alignment by feeding\nMAX_FOLIO_VMEMMAP_ALIGN directly into VMEMMAP_ADDR_ALIGN. However,\nMAX_FOLIO_VMEMMAP_ALIGN is measured in bytes of struct page storage,\nwhereas VMEMMAP_ADDR_ALIGN is used to align a physical address.\n\nThe mask-based compound_info encoding requires pfn_to_page(0) to be\nnaturally aligned to MAX_FOLIO_VMEMMAP_ALIGN. Commit 9f94db4c7eaa\n(\"mm/sparse: check memmap alignment for compound_info_has_mask()\") added a\ncheck for that requirement and exposed the unit mismatch on systems such\nas QEMU virt, where the DRAM base is not aligned to MAX_FOLIO_NR_PAGES *\nPAGE_SIZE.\n\nHere is the log:\n[ 0.000000][ C0] ------------[ cut here ]------------\n[ 0.000000][ C0] WARNING: mm/sparse.c:365 at sparse_init+0x58a/0x6fe, CPU#0: swapper/0\n[ 0.000000][ C0] Modules linked in:\n[ 0.000000][ C0] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 7.2.0-rc3-g1d8304bdd65f #2 PREEMPT \n[ 0.000000][ C0] Hardware name: riscv-virtio,qemu (DT)\n[ 0.000000][ C0] epc : sparse_init+0x58a/0x6fe\n[ 0.000000][ C0] ra : sparse_init+0x58a/0x6fe\n[ 0.000000][ C0] epc : ffffffff86851c88 ra : ffffffff86851c88 sp : ffffffff88807a30\n[ 0.000000][ C0] gp : ffffffff8a3bf240 tp : ffffffff88842080 t0 : ff600000ffab6000\n[ 0.000000][ C0] t1 : 000000017fab6000 t2 : 65203a6573726363 s0 : ffffffff88807bc0\n[ 0.000000][ C0] s1 : 000000000e000000 a0 : 0000000000000007 a1 : 0000000000000000\n[ 0.000000][ C0] a2 : 0000000000000002 a3 : ffffffff86851c88 a4 : 0000000000000000\n[ 0.000000][ C0] a5 : ffffffff88843080 a6 : 0000000000000003 a7 : 0000000000000000\n[ 0.000000][ C0] s2 : ff60000000000000 s3 : 0040000000000000 s4 : 0004000000000000\n[ 0.000000][ C0] s5 : ffffffff8a4d92e0 s6 : ff600000ffab55e0 s7 : ffffffff88384d00\n[ 0.000000][ C0] s8 : 0000000000000003 s9 : ffffffff88384cc1 s10: ffffffff88384cc0\n[ 0.000000][ C0] s11: ffffffff8a4daae0 t3 : ffffffff915e8b20 t4 : ffffffff915e8b20\n[ 0.000000][ C0] t5 : ffffffff915e8b20 t6 : ffffffff915e8bc8 ssp : 0000000000000000\n[ 0.000000][ C0] status: 0000000200000100 badaddr: ffffffff86851c88 cause: 0000000000000003\n[ 0.000000][ C0] [<ffffffff86851c88>] sparse_init+0x58a/0x6fe\n[ 0.000000][ C0] [<ffffffff8683d396>] mm_core_init_early+0x116/0x1e30\n[ 0.000000][ C0] [<ffffffff86801edc>] start_kernel+0xd2/0x848\n\nConvert MAX_FOLIO_VMEMMAP_ALIGN to the equivalent physical alignment\nbefore using it in VMEMMAP_ADDR_ALIGN. This keeps the existing\nround_down() logic while making the resulting vmemmap base satisfy the\nmask-alignment requirement."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The flaw is set during early boot in arch/riscv/mm/init.c setup_bootmem()/sparse_init(), and runtime impact is reached through local memory-management syscalls (mmap, page faults, compound folio allocation) invoking compound_head(); no network, adjacent-network, or remote protocol path exists.\nAC:L - On affected RISC-V 64 kernels with HUGETLB/HVO enabled (RISC-V defconfig) and DRAM bases such as QEMU virt where phys_ram_base is not aligned to MAX_FOLIO_NR_PAGES*PAGE_SIZE, the wrong vmemmap_start_pfn and misaligned pfn_to_page(0) occur deterministically every boot without races or attacker-uncontrollable layout.\nPR:L - The broken vmemmap alignment is established automatically at boot before any credentials exist; once running, an unprivileged local user can trigger compound folio allocation and freeing (anonymous mmap, THP, hugetlbfs) that exercise mask-based compound_head() with no capability or namespace gate.\nUI:N - No victim interaction is required beyond normal operation of an already-affected system; the attacker does not need another user to mount filesystems, open devices, or perform discretionary actions to reach the broken compound-page paths.\nS:U - Impact is kernel memory and page-metadata corruption within the host kernel security authority; it does not cross a VM, hypervisor, IOMMU/DMA, or sandbox boundary into a separate security domain.\nC:H - Misaligned pfn_to_page(0) breaks compound_info mask decoding so compound_head() can map tail struct pages to incorrect heads, enabling out-of-bounds reads of adjacent kernel page metadata and folio contents through routine MM operations (get_user_pages, compaction, isolation).\nI:H - Resolving the wrong compound head corrupts folio refcount, mapping, and LRU state and directs kernel read/write operations to unintended physical pages, providing a defensible arbitrary kernel-memory corruption primitive leveragable for privilege escalation.\nA:H - Incorrect compound_head() resolution can oops or panic the kernel during page isolation, compaction, THP, hugetlb, and I/O pin paths; sparse_init() VM_WARN_ON_ONCE on standard QEMU virt confirms the alignment violation is real on common RISC-V deployments."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/riscv/mm/init.c"], "versions": [{"version": "476849b0fba4450f5adf22196bcff9c24c673bc4", "lessThan": "11ad86830a78ea4e1942afc73c10e4ca8e69e03f", "status": "affected", "versionType": "git"}, {"version": "476849b0fba4450f5adf22196bcff9c24c673bc4", "lessThan": "45ebe4540817cb540a59e4dc04014ac5dddc9990", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/riscv/mm/init.c"], "versions": [{"version": "7.1", "status": "affected"}, {"version": "0", "lessThan": "7.1", "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": "7.1", "versionEndExcluding": "7.1.8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/11ad86830a78ea4e1942afc73c10e4ca8e69e03f"}, {"url": "https://git.kernel.org/stable/c/45ebe4540817cb540a59e4dc04014ac5dddc9990"}], "title": "riscv/mm: use physical alignment for vmemmap_start_pfn", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["arch/riscv/mm/init.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "11ad86830a78ea4e1942afc73c10e4ca8e69e03f", "status": "affected", "version": "476849b0fba4450f5adf22196bcff9c24c673bc4", "versionType": "git"}, {"lessThan": "45ebe4540817cb540a59e4dc04014ac5dddc9990", "status": "affected", "version": "476849b0fba4450f5adf22196bcff9c24c673bc4", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["arch/riscv/mm/init.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.1"}, {"lessThan": "7.1", "status": "unaffected", "version": "0", "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\nriscv/mm: use physical alignment for vmemmap_start_pfn\n\nRISC-V computes vmemmap_start_pfn by rounding phys_ram_base down to\nVMEMMAP_ADDR_ALIGN. That alignment must therefore be expressed in the\nphysical-address domain.\n\nCommit 476849b0fba4 (\"riscv/mm: align vmemmap to maximal folio size\")\nattempted to account for the maximal folio alignment by feeding\nMAX_FOLIO_VMEMMAP_ALIGN directly into VMEMMAP_ADDR_ALIGN. However,\nMAX_FOLIO_VMEMMAP_ALIGN is measured in bytes of struct page storage,\nwhereas VMEMMAP_ADDR_ALIGN is used to align a physical address.\n\nThe mask-based compound_info encoding requires pfn_to_page(0) to be\nnaturally aligned to MAX_FOLIO_VMEMMAP_ALIGN. Commit 9f94db4c7eaa\n(\"mm/sparse: check memmap alignment for compound_info_has_mask()\") added a\ncheck for that requirement and exposed the unit mismatch on systems such\nas QEMU virt, where the DRAM base is not aligned to MAX_FOLIO_NR_PAGES *\nPAGE_SIZE.\n\nHere is the log:\n[ 0.000000][ C0] ------------[ cut here ]------------\n[ 0.000000][ C0] WARNING: mm/sparse.c:365 at sparse_init+0x58a/0x6fe, CPU#0: swapper/0\n[ 0.000000][ C0] Modules linked in:\n[ 0.000000][ C0] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 7.2.0-rc3-g1d8304bdd65f #2 PREEMPT \n[ 0.000000][ C0] Hardware name: riscv-virtio,qemu (DT)\n[ 0.000000][ C0] epc : sparse_init+0x58a/0x6fe\n[ 0.000000][ C0] ra : sparse_init+0x58a/0x6fe\n[ 0.000000][ C0] epc : ffffffff86851c88 ra : ffffffff86851c88 sp : ffffffff88807a30\n[ 0.000000][ C0] gp : ffffffff8a3bf240 tp : ffffffff88842080 t0 : ff600000ffab6000\n[ 0.000000][ C0] t1 : 000000017fab6000 t2 : 65203a6573726363 s0 : ffffffff88807bc0\n[ 0.000000][ C0] s1 : 000000000e000000 a0 : 0000000000000007 a1 : 0000000000000000\n[ 0.000000][ C0] a2 : 0000000000000002 a3 : ffffffff86851c88 a4 : 0000000000000000\n[ 0.000000][ C0] a5 : ffffffff88843080 a6 : 0000000000000003 a7 : 0000000000000000\n[ 0.000000][ C0] s2 : ff60000000000000 s3 : 0040000000000000 s4 : 0004000000000000\n[ 0.000000][ C0] s5 : ffffffff8a4d92e0 s6 : ff600000ffab55e0 s7 : ffffffff88384d00\n[ 0.000000][ C0] s8 : 0000000000000003 s9 : ffffffff88384cc1 s10: ffffffff88384cc0\n[ 0.000000][ C0] s11: ffffffff8a4daae0 t3 : ffffffff915e8b20 t4 : ffffffff915e8b20\n[ 0.000000][ C0] t5 : ffffffff915e8b20 t6 : ffffffff915e8bc8 ssp : 0000000000000000\n[ 0.000000][ C0] status: 0000000200000100 badaddr: ffffffff86851c88 cause: 0000000000000003\n[ 0.000000][ C0] [<ffffffff86851c88>] sparse_init+0x58a/0x6fe\n[ 0.000000][ C0] [<ffffffff8683d396>] mm_core_init_early+0x116/0x1e30\n[ 0.000000][ C0] [<ffffffff86801edc>] start_kernel+0xd2/0x848\n\nConvert MAX_FOLIO_VMEMMAP_ALIGN to the equivalent physical alignment\nbefore using it in VMEMMAP_ADDR_ALIGN. This keeps the existing\nround_down() logic while making the resulting vmemmap base satisfy the\nmask-alignment requirement."}], "id": "CVE-2026-80682", "lastModified": "2026-08-29T07:16:50.703", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-08-28T08:16:53.607", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/11ad86830a78ea4e1942afc73c10e4ca8e69e03f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/45ebe4540817cb540a59e4dc04014ac5dddc9990"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[476849b0fba4450f5adf22196bcff9c24c673bc4,11ad86830a78ea4e1942afc73c10e4ca8e69e03f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[476849b0fba4450f5adf22196bcff9c24c673bc4,45ebe4540817cb540a59e4dc04014ac5dddc9990)"}}], "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": "7.1"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,7.1)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.8,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2,*]"}}], "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": "2026-08-28T11:30:06.783686+00:00", "updated": "2026-08-29T07:45:06.300851+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-665", "CWE-784"]}