{"cve":"CVE-2026-98254","nvd":{"published":"2026-10-06T09:18:14.057","modified":"2026-10-19T10:18:26.380","status":"Received","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/0219b72f5c209732b2f03a8cc0d7240b5e428a99","https://git.kernel.org/stable/c/6e53b4d6afbde626255805d438cabb1cac482445","https://git.kernel.org/stable/c/aa4709813b29db89f2307f968db5d24925dcdeb1","https://git.kernel.org/stable/c/b7d7914a9ae3097e63d113007e4fb44d33d515b1"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:57:46.668721662+00:00"},"epss":{"cve":"CVE-2026-98254","score":0.00129,"percentile":0.02487,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}