{"cve":"CVE-2026-89751","nvd":{"published":"2026-09-11T20:20:06.013","modified":"2026-10-19T09:18:18.113","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/tdx: Fix off-by-one in port I/O handling\n\nhandle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use:\n\n    u64 mask = GENMASK(BITS_PER_BYTE * size, 0);\n\nGENMASK(h, l) includes bit h. For size=1 (INB), this produces\nGENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8\nbits). The mask is one bit too wide for all I/O sizes.\n\nFix the mask calculation.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25","https://git.kernel.org/stable/c/220011fe95fc78b2bc2d7d43893bc73957a5c811","https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a","https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8","https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-89751","score":0.00173,"percentile":0.06636,"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."]}