{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-80954",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-26T14:34:25.804Z",
        "datePublished": "2026-09-11T19:42:23.169Z",
        "dateUpdated": "2026-10-19T08:45:38.169Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T08:45:38.169Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ni3c: Fix unlocked dereference of dev->desc in i3c_device_get_supported_xfer_mode()\n\ni3c_device_get_supported_xfer_mode() uses dev->desc to obtain the\nmaster controller.  However, dev->desc must not be dereferenced unless\nbus->lock is held, and this function does not take that lock.\n\nThe function only needs access to the master controller associated with\nthe device's bus.  Use dev->bus instead, which is always valid for the\nlifetime of the device and does not require dereferencing dev->desc."
                }
            ],
            "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 unlocked desc dereference is reached from local IIO sysfs reads of an I3C-backed MMC5633 magnetometer (in_magn_*_raw/in_temp_raw via iio_read_channel_info) and from /dev/iio:deviceN; I3C is an on-board host bus with no network or Bluetooth packet path.\nAC:L - A local attacker can loop those IIO reads while concurrently forcing Dynamic Address Assignment, which replaces and kfree()s i3c_dev_desc (hot-join, MIPI I3C HCI/Renesas resume re-DAA, or sysfs do_daa). The attacker drives the unlocked-read side and can retry until it races with DAA.\nPR:L - IIO channel attributes are created 0444/0644 and iio_read_channel_info performs no capability check, so an unprivileged local user on Android, automotive, or embedded I3C boards can invoke mmc5633_read_raw without init-namespace root.\nUI:N - The attacker performs their own sysfs or IIO chardev reads against an already-present I3C device; no separate victim action such as plugging hardware or mounting a filesystem is required.\nS:U - The use-after-free corrupts an i3c_dev_desc in the host kernel heap and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - Unlocked load of dev->desc races with DAA's i3c_master_free_i3c_dev(), so i3c_dev_get_master() walks a freed descriptor (common.master then this->info.hdr_cap). Reclaiming that object yields a kernel read primitive; UAF is High confidentiality.\nI:H - A sprayed fake i3c_dev_desc lets the nested pointer walk interpret attacker-controlled heap as kernel objects, enabling further writes and control-flow hijack through the same freed slab; UAF is High integrity.\nA:H - Dereferencing a NULL or freed desc in i3c_dev_get_master() causes a kernel oops or panic even without a full exploit, so availability impact is High."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/i3c/device.c",
                        "drivers/i3c/internals.h",
                        "drivers/i3c/master.c"
                    ],
                    "versions": [
                        {
                            "version": "256a21743d911f94ce92fe28f793cd586f3860b2",
                            "lessThan": "251db58324ea4792c3f9f692ab09be148e051969",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "256a21743d911f94ce92fe28f793cd586f3860b2",
                            "lessThan": "8bed7f4fa710914b7f05fd59998316bfb4d43385",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/i3c/device.c",
                        "drivers/i3c/internals.h",
                        "drivers/i3c/master.c"
                    ],
                    "versions": [
                        {
                            "version": "6.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.4",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "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": "6.19",
                                    "versionEndExcluding": "7.2.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.19",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/251db58324ea4792c3f9f692ab09be148e051969"
                },
                {
                    "url": "https://git.kernel.org/stable/c/8bed7f4fa710914b7f05fd59998316bfb4d43385"
                }
            ],
            "title": "i3c: Fix unlocked dereference of dev->desc in i3c_device_get_supported_xfer_mode()",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}