{"cve":"CVE-2026-80951","nvd":{"published":"2026-09-11T20:19:00.803","modified":"2026-10-19T09:17:26.477","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ni3c: master: svc: bound IBI payload to the requested max_payload_len\n\nsvc_i3c_master_handle_ibi() reads the IBI payload from the RX FIFO into\nthe IBI slot. The loop is bounded by the hardware FIFO size\n(SVC_I3C_FIFO_SIZE), not by the slot size.\n\nslot->data points into the IBI pool, which i3c_generic_ibi_alloc_pool()\nsizes at max_payload_len per slot. svc_i3c_master_request_ibi() only\nrejects a max_payload_len larger than SVC_I3C_FIFO_SIZE, so a driver can\nrequest a smaller one. mctp-i3c requests 1. Each readsb() then copies the\ncontroller RXCOUNT bytes (up to 31) with no check against the slot size.\nA device that sends more bytes than the slot holds writes past\nslot->data, an out-of-bounds write into the IBI pool.\n\nBound the loop by dev->ibi->max_payload_len and clamp each read to the\nspace left in the slot, the same way dw-i3c does. A device can still send\nmore than the requested payload. Flush the leftover bytes from the RX FIFO\nso they do not leak into the next transfer.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/35aa6730b8c5626b879a4e893fe664f59bf07d7f","https://git.kernel.org/stable/c/5697d779577e2786ff3348ae9b77020ac0cf0aab","https://git.kernel.org/stable/c/7c099b0b292a68d0ef558527945dbfb756fbf893","https://git.kernel.org/stable/c/7cc5ba756bc1cfffab9cb2695742f9f479dc73f7","https://git.kernel.org/stable/c/aac3c5aababc7fb69d5bf5b0cc52d308574e3a8c"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-80951","score":0.00211,"percentile":0.11296,"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."]}