{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63962",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T07:54:57.024Z",
        "datePublished": "2026-07-19T14:55:51.682Z",
        "dateUpdated": "2026-07-20T06:41:42.766Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-07-20T06:41:42.766Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: typec: tcpm: bound altmode_desc[] per iteration in svdm_consume_modes()\n\nsvdm_consume_modes() checks pmdata->altmodes against the array size once\nbefore the loop over the count, but forgot to check the bound at every\npoint in the loop.\n\nIn the well-behaved SVDM discovery flow this is harmless because each of\nat most SVID_DISCOVERY_MAX SVIDs contributes at most MODE_DISCOVERY_MAX\nmodes, exactly filling altmode_desc[ALTMODE_DISCOVERY_MAX].  But the\nCMDT_RSP_ACK handler in tcpm_pd_svdm() does not correlate an incoming\nACK with any request the port actually sent.  Once port->partner is set,\nan unsolicited Discover Modes ACK is consumed unconditionally.  A broken\nor malicious port partner can therefore drive altmodes to\nALTMODE_DISCOVERY_MAX - 1 via the normal flow, and then send one extra\nDiscover Modes ACK with seven VDOs.  Because the pre-loop check passes,\nthe loop could then writes up to five entries past altmode_desc[].  For\nmode_data_prime the next field in struct tcpm_port is the\npartner_altmode[] pointer array, which then receives partner-chosen\nSVID/VDO bytes.\n\nMove the bound check inside the loop so the array can never be indexed\npast ALTMODE_DISCOVERY_MAX regardless of how many VDOs the partner\nsupplies or how the function was reached."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/usb/typec/tcpm/tcpm.c"
                    ],
                    "versions": [
                        {
                            "version": "4ab8c18d4d67321cc7b660559de17511d4fc0237",
                            "lessThan": "845598b154b9a92e9d279fafafa9405c121ae805",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "4ab8c18d4d67321cc7b660559de17511d4fc0237",
                            "lessThan": "4505f33dab56c274e82f47f94bf60a8cbf8f4b42",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "4ab8c18d4d67321cc7b660559de17511d4fc0237",
                            "lessThan": "cbad85b446c06adbc5e5bed565871bb918ce9d32",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "4ab8c18d4d67321cc7b660559de17511d4fc0237",
                            "lessThan": "3389c149c68c3fea61910ad5d34f7bf3bff44e32",
                            "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/usb/typec/tcpm/tcpm.c"
                    ],
                    "versions": [
                        {
                            "version": "4.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "4.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.93",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.35",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.12",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "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": "4.19",
                                    "versionEndExcluding": "6.12.93"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.19",
                                    "versionEndExcluding": "6.18.35"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.19",
                                    "versionEndExcluding": "7.0.12"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.19",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/845598b154b9a92e9d279fafafa9405c121ae805"
                },
                {
                    "url": "https://git.kernel.org/stable/c/4505f33dab56c274e82f47f94bf60a8cbf8f4b42"
                },
                {
                    "url": "https://git.kernel.org/stable/c/cbad85b446c06adbc5e5bed565871bb918ce9d32"
                },
                {
                    "url": "https://git.kernel.org/stable/c/3389c149c68c3fea61910ad5d34f7bf3bff44e32"
                }
            ],
            "title": "usb: typec: tcpm: bound altmode_desc[] per iteration in svdm_consume_modes()",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}