{"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": "2026-04-24T14:42:36.191Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-04-24T14:42:36.191Z"}, "descriptions": [{"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."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/usb/gadget/function/f_ncm.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "8757a2593631443648218244b9788e193ae0fdc1", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "6762f8a95772265dd0c2ffe7f400493f3115b135", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d58ba8f6546232f8414f396c189297dbee03f1a7", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "74908b0318d1df1188457040b8714ff4d4b68126", "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/gadget/function/f_ncm.c"], "versions": [{"version": "6.12.83", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.24", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.14", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.1", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12.83"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.18.24"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.19.14"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.0.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/8757a2593631443648218244b9788e193ae0fdc1"}, {"url": "https://git.kernel.org/stable/c/6762f8a95772265dd0c2ffe7f400493f3115b135"}, {"url": "https://git.kernel.org/stable/c/d58ba8f6546232f8414f396c189297dbee03f1a7"}, {"url": "https://git.kernel.org/stable/c/74908b0318d1df1188457040b8714ff4d4b68126"}], "title": "usb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"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."}], "id": "CVE-2026-31617", "lastModified": "2026-04-24T17:51:40.810", "metrics": {}, "published": "2026-04-24T15:16:40.973", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6762f8a95772265dd0c2ffe7f400493f3115b135"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/74908b0318d1df1188457040b8714ff4d4b68126"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8757a2593631443648218244b9788e193ae0fdc1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d58ba8f6546232f8414f396c189297dbee03f1a7"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{}

{}