{"api_version":"1","generated_at":"2026-10-22T00:46:29+00:00","cve":"CVE-2026-98254","urls":{"html":"https://cve.report/CVE-2026-98254","api":"https://cve.report/api/cve/CVE-2026-98254.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98254","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98254"},"summary":{"title":"swiotlb: use the adjusted address for the highmem page lookup","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nswiotlb: use the adjusted address for the highmem page lookup\n\nswiotlb_bounce() reads the page frame number from the slot's recorded\norig_addr, then advances orig_addr by tlb_offset to reach the address\nthe caller asked about. The highmem branch mixes the two: the offset\nwithin the page comes from the adjusted address, the page from the value\nbefore it.\n\nOnce the adjustment crosses a page boundary the pair no longer describes\none location, and the whole copy lands one page below the intended one\nfor a positive tlb_offset, one above for a negative one. DMA_FROM_DEVICE\nwrites the device data over the wrong page and leaves the intended one\nstale, DMA_TO_DEVICE feeds the device from a page the mapping may not\ncover. Partial syncs through dma_sync_single_range_for_*() are what make\ntlb_offset non-zero.\n\nThe branch test is picked the same way, so a slot recorded in lowmem can\nbe adjusted into highmem and the lowmem path then hands a highmem\naddress to phys_to_virt().\n\nTake both from orig_addr once it is final and keep pfn in the branch\nthat uses it. PhysHighMem() asks the question straight from the address,\nas dma-debug already does.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-06 09:18:14","updated_at":"2026-10-19 10:18:26"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/6e53b4d6afbde626255805d438cabb1cac482445","name":"https://git.kernel.org/stable/c/6e53b4d6afbde626255805d438cabb1cac482445","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/aa4709813b29db89f2307f968db5d24925dcdeb1","name":"https://git.kernel.org/stable/c/aa4709813b29db89f2307f968db5d24925dcdeb1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b7d7914a9ae3097e63d113007e4fb44d33d515b1","name":"https://git.kernel.org/stable/c/b7d7914a9ae3097e63d113007e4fb44d33d515b1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0219b72f5c209732b2f03a8cc0d7240b5e428a99","name":"https://git.kernel.org/stable/c/0219b72f5c209732b2f03a8cc0d7240b5e428a99","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98254","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98254","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5f89468e2f060031cd89fd4287298e0eaf246bf6 6e53b4d6afbde626255805d438cabb1cac482445 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5f89468e2f060031cd89fd4287298e0eaf246bf6 aa4709813b29db89f2307f968db5d24925dcdeb1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5f89468e2f060031cd89fd4287298e0eaf246bf6 0219b72f5c209732b2f03a8cc0d7240b5e428a99 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5f89468e2f060031cd89fd4287298e0eaf246bf6 b7d7914a9ae3097e63d113007e4fb44d33d515b1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e6108147dd91b94d1979b110f265710c254c99d5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e77b796eb9b7ca3c1c0d574d0c155f55b59ca8d5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.10.47 5.11 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.12.14 5.13 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.13","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.13 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.112 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.54 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.8 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"98254","cve":"CVE-2026-98254","epss":"0.001750000","percentile":"0.063790000","score_date":"2026-10-06","updated_at":"2026-10-07 00:14:55"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/dma/swiotlb.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"6e53b4d6afbde626255805d438cabb1cac482445","status":"affected","version":"5f89468e2f060031cd89fd4287298e0eaf246bf6","versionType":"git"},{"lessThan":"aa4709813b29db89f2307f968db5d24925dcdeb1","status":"affected","version":"5f89468e2f060031cd89fd4287298e0eaf246bf6","versionType":"git"},{"lessThan":"0219b72f5c209732b2f03a8cc0d7240b5e428a99","status":"affected","version":"5f89468e2f060031cd89fd4287298e0eaf246bf6","versionType":"git"},{"lessThan":"b7d7914a9ae3097e63d113007e4fb44d33d515b1","status":"affected","version":"5f89468e2f060031cd89fd4287298e0eaf246bf6","versionType":"git"},{"status":"affected","version":"e6108147dd91b94d1979b110f265710c254c99d5","versionType":"git"},{"status":"affected","version":"e77b796eb9b7ca3c1c0d574d0c155f55b59ca8d5","versionType":"git"},{"lessThan":"5.11","status":"affected","version":"5.10.47","versionType":"semver"},{"lessThan":"5.13","status":"affected","version":"5.12.14","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/dma/swiotlb.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.13"},{"lessThan":"5.13","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.112","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.54","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.112","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.54","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.8","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.47","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nswiotlb: use the adjusted address for the highmem page lookup\n\nswiotlb_bounce() reads the page frame number from the slot's recorded\norig_addr, then advances orig_addr by tlb_offset to reach the address\nthe caller asked about. The highmem branch mixes the two: the offset\nwithin the page comes from the adjusted address, the page from the value\nbefore it.\n\nOnce the adjustment crosses a page boundary the pair no longer describes\none location, and the whole copy lands one page below the intended one\nfor a positive tlb_offset, one above for a negative one. DMA_FROM_DEVICE\nwrites the device data over the wrong page and leaves the intended one\nstale, DMA_TO_DEVICE feeds the device from a page the mapping may not\ncover. Partial syncs through dma_sync_single_range_for_*() are what make\ntlb_offset non-zero.\n\nThe branch test is picked the same way, so a slot recorded in lowmem can\nbe adjusted into highmem and the lowmem path then hands a highmem\naddress to phys_to_virt().\n\nTake both from orig_addr once it is final and keep pfn in the branch\nthat uses it. PhysHighMem() asks the question straight from the address,\nas dma-debug already does."}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - The defect is in swiotlb_bounce(), reached only via __swiotlb_sync_single_for_cpu/_for_device from a driver's dma_sync_single_range_for_*() on a bounced buffer. No protocol message carries malformed input, and a local user can only cause it by doing I/O on a highmem buffer through such a driver.\nAC:L - Not used; the AC line below is the real value.\nPR:L - The attacker needs an ordinary local account to issue I/O whose buffers (user or page-cache pages, which can be highmem) go through an affected device's streaming DMA mapping. No capability check on the swiotlb sync path stands in the way.\nUI:N - Once the attacker's own I/O drives the partial-sync pattern, no victim action is needed. The bounce runs inside the driver's sync call.\nS:U - The bad copy is done by the kernel's own swiotlb code into kernel-managed physical memory. No IOMMU, VM or other boundary is crossed beyond the kernel's own authority.\nC:H - On DMA_TO_DEVICE, memcpy_from_page() uses pfn_to_page(PFN_DOWN(old orig_addr)) and feeds the device a whole neighbouring physical page the mapping does not cover. This can expose unrelated kernel or user data to the device.\nI:H - On DMA_FROM_DEVICE, memcpy_to_page() writes device data over the page next to the intended one, corrupting arbitrary neighbouring memory. Separately, a lowmem slot shifted into highmem sends a highmem address to phys_to_virt() and memcpy() through a bogus pointer.\nA:H - Overwriting an unrelated physical page, or calling memcpy() on a bogus phys_to_virt() pointer for a highmem address, can corrupt kernel state or fault and oops the kernel."}]}],"providerMetadata":{"dateUpdated":"2026-10-19T09:16:25.551Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/6e53b4d6afbde626255805d438cabb1cac482445"},{"url":"https://git.kernel.org/stable/c/aa4709813b29db89f2307f968db5d24925dcdeb1"},{"url":"https://git.kernel.org/stable/c/0219b72f5c209732b2f03a8cc0d7240b5e428a99"},{"url":"https://git.kernel.org/stable/c/b7d7914a9ae3097e63d113007e4fb44d33d515b1"}],"title":"swiotlb: use the adjusted address for the highmem page lookup","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98254","datePublished":"2026-10-06T08:45:20.736Z","dateReserved":"2026-09-25T10:25:14.331Z","dateUpdated":"2026-10-19T09:16:25.551Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-06 09:18:14","lastModifiedDate":"2026-10-19 10:18:26","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98254","Ordinal":"1","Title":"swiotlb: use the adjusted address for the highmem page lookup","CVE":"CVE-2026-98254","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98254","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nswiotlb: use the adjusted address for the highmem page lookup\n\nswiotlb_bounce() reads the page frame number from the slot's recorded\norig_addr, then advances orig_addr by tlb_offset to reach the address\nthe caller asked about. The highmem branch mixes the two: the offset\nwithin the page comes from the adjusted address, the page from the value\nbefore it.\n\nOnce the adjustment crosses a page boundary the pair no longer describes\none location, and the whole copy lands one page below the intended one\nfor a positive tlb_offset, one above for a negative one. DMA_FROM_DEVICE\nwrites the device data over the wrong page and leaves the intended one\nstale, DMA_TO_DEVICE feeds the device from a page the mapping may not\ncover. Partial syncs through dma_sync_single_range_for_*() are what make\ntlb_offset non-zero.\n\nThe branch test is picked the same way, so a slot recorded in lowmem can\nbe adjusted into highmem and the lowmem path then hands a highmem\naddress to phys_to_virt().\n\nTake both from orig_addr once it is final and keep pfn in the branch\nthat uses it. PhysHighMem() asks the question straight from the address,\nas dma-debug already does.","Type":"Description","Title":"swiotlb: use the adjusted address for the highmem page lookup"}]}}}