{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-31617",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-03-09T15:48:24.123Z",
        "datePublished": "2026-04-24T14:42:36.191Z",
        "dateUpdated": "2026-08-06T12:08:53.324Z"
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                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-06-14T17:43:02.575Z"
            },
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                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb()\n\nThe block_len read from the host-supplied NTB header is checked against\nntb_max but has no lower bound. When block_len is smaller than\nopts->ndp_size, the bounds check of:\n\tndp_index > (block_len - opts->ndp_size)\nwill underflow producing a huge unsigned value that ndp_index can never\nexceed, defeating the check entirely.\n\nThe same underflow occurs in the datagram index checks against block_len\n- opts->dpe_size.  With those checks neutered, a malicious USB host can\nchoose ndp_index and datagram offsets that point past the actual\ntransfer, and the skb_put_data() copies adjacent kernel memory into the\nnetwork skb.\n\nFix this by rejecting block lengths that cannot hold at least the NTB\nheader plus one NDP.  This will make block_len - opts->ndp_size and\nblock_len - opts->dpe_size both well-defined.\n\nCommit 8d2b1a1ec9f5 (\"CDC-NCM: avoid overflow in sanity checking\") fixed\na related class of issues on the host side of NCM."
                }
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                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/usb/gadget/function/f_ncm.c"
                    ],
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                            "status": "affected",
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                            "lessThan": "74908b0318d1df1188457040b8714ff4d4b68126",
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                            "status": "affected",
                            "versionType": "git"
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                        {
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                            "status": "affected",
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                            "status": "affected",
                            "versionType": "git"
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                        {
                            "version": "471b23586387a32857778c511be60ab31c98dcfd",
                            "status": "affected",
                            "versionType": "git"
                        },
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                            "version": "4f529c4d1e436230d3af7c09a3239677a14d2b46",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "ae6a5394d9fbe118bc95cfe376d6a9d91d7547e8",
                            "status": "affected",
                            "versionType": "git"
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                            "status": "affected",
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                            "status": "affected",
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                            "status": "affected",
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                    "vendor": "Linux",
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                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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                            "status": "affected"
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                        {
                            "version": "0",
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                            "status": "unaffected",
                            "versionType": "semver"
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                            "status": "unaffected",
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                            "status": "unaffected",
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                            "status": "unaffected",
                            "versionType": "semver"
                        },
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                            "status": "unaffected",
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                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.24",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
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                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
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                            "version": "7.0.1",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
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                    "url": "https://git.kernel.org/stable/c/8f993d30b95dc9557a8a96ceca11abed674c8acb"
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            "title": "usb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb()",
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}