{"id":"CVE-2026-68368","title":"usb: gadget: f_ncm: validate datagram bounds in ncm_unwrap_ntb()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: validate datagram bounds in ncm_unwrap_ntb()\n\nWhen unpacking host-supplied NTBs, ncm_unwrap_ntb() checks datagram length\nagainst frame_max but does …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 35d15bbaec0557330e774ec31412ef508de6e0e0","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 6b2be489eaa6293e60549005d91f15ceb150510f","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < f87ed889f0f7417b8938c98d8833f559b755373c","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < e07751d0527ccc2a1c32eb0b0b7da3b4b9b5381f","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < fff1059d139ef798bab917990524faaf25854ca8","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 40c706a0224bde194667e3378c689b542fec4b44","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 41fd5f2fb0027d3773ae949e3247c2e0a2a7fe5c","Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 1febec7e47cdcd01f43fb0211094e3010474666e","Linux f7e0611e207d8908c4f2858e244370529a76dbf7","Linux b88ad6e714284b33a47834f5f2a294c2b37c66aa","Linux 471b23586387a32857778c511be60ab31c98dcfd","Linux 4f529c4d1e436230d3af7c09a3239677a14d2b46","Linux ae6a5394d9fbe118bc95cfe376d6a9d91d7547e8","Linux 5bdf93a2f5459f944b416b188178ca4a92fd206f","Linux ff3ba016263ee93a1c6209bf5ab1599de7ab1512","Linux e7ca00f35d8a17af1ae19d529193ebc21bfda164","Linux >= 4.9.235 < 4.10","Linux >= 4.14.196 < 4.15","Linux >= 4.19.143 < 4.20","Linux >= 5.4.62 < 5.5","Linux >= 5.8.6 < 5.9","Linux >= 4.14.328 < 4.15","Linux >= 4.19.297 < 4.20","Linux >= 5.4.259 < 5.5","Linux 5.9"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:48:23.014514Z"},"published":"2026-08-10","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:55:14.928Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68368","references":[{"url":"https://git.kernel.org/stable/c/35d15bbaec0557330e774ec31412ef508de6e0e0"},{"url":"https://git.kernel.org/stable/c/6b2be489eaa6293e60549005d91f15ceb150510f"},{"url":"https://git.kernel.org/stable/c/f87ed889f0f7417b8938c98d8833f559b755373c"},{"url":"https://git.kernel.org/stable/c/e07751d0527ccc2a1c32eb0b0b7da3b4b9b5381f"},{"url":"https://git.kernel.org/stable/c/fff1059d139ef798bab917990524faaf25854ca8"},{"url":"https://git.kernel.org/stable/c/40c706a0224bde194667e3378c689b542fec4b44"},{"url":"https://git.kernel.org/stable/c/41fd5f2fb0027d3773ae949e3247c2e0a2a7fe5c"},{"url":"https://git.kernel.org/stable/c/1febec7e47cdcd01f43fb0211094e3010474666e"}],"tags":["cve.org"],"epss":0.00216,"epssPercentile":0.12154,"ingestedAt":"2026-11-06T18:00:12.606Z","slug":"CVE-2026-68368","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: validate datagram bounds in ncm_unwrap_ntb()\n\nWhen unpacking host-supplied NTBs, ncm_unwrap_ntb() checks datagram length\nagainst frame_max but does not verify that the datagram fits within the\ndeclared block length. Additionally, when decoding multiple NTBs from a\nsingle socket buffer, subsequent block lengths are not checked against the\nactual remaining buffer data.\n\nWith these checks missing, a malicious USB host can specify datagram\noffsets and lengths that point beyond the block, or supply secondary NTB\nheaders declaring lengths larger than the buffer. skb_put_data() then\ncopies adjacent kernel memory from skb_shared_info into the network skb.\n\nFix this by verifying that sufficient buffer space remains for the NTB\nheader before parsing, handling zero-length block declarations, ensuring\nthat block lengths never exceed the remaining buffer space, and verifying\nthat each datagram payload stays strictly within the block boundary.\n\n## Affected\n\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 35d15bbaec0557330e774ec31412ef508de6e0e0`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 6b2be489eaa6293e60549005d91f15ceb150510f`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < f87ed889f0f7417b8938c98d8833f559b755373c`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < e07751d0527ccc2a1c32eb0b0b7da3b4b9b5381f`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < fff1059d139ef798bab917990524faaf25854ca8`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 40c706a0224bde194667e3378c689b542fec4b44`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 41fd5f2fb0027d3773ae949e3247c2e0a2a7fe5c`\n- `Linux >= 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 < 1febec7e47cdcd01f43fb0211094e3010474666e`\n- `Linux f7e0611e207d8908c4f2858e244370529a76dbf7`\n- `Linux b88ad6e714284b33a47834f5f2a294c2b37c66aa`\n- `Linux 471b23586387a32857778c511be60ab31c98dcfd`\n- `Linux 4f529c4d1e436230d3af7c09a3239677a14d2b46`\n- `Linux ae6a5394d9fbe118bc95cfe376d6a9d91d7547e8`\n- `Linux 5bdf93a2f5459f944b416b188178ca4a92fd206f`\n- `Linux ff3ba016263ee93a1c6209bf5ab1599de7ab1512`\n- `Linux e7ca00f35d8a17af1ae19d529193ebc21bfda164`\n- `Linux >= 4.9.235 < 4.10`\n- `Linux >= 4.14.196 < 4.15`\n- `Linux >= 4.19.143 < 4.20`\n- `Linux >= 5.4.62 < 5.5`\n- `Linux >= 5.8.6 < 5.9`\n- `Linux >= 4.14.328 < 4.15`\n- `Linux >= 4.19.297 < 4.20`\n- `Linux >= 5.4.259 < 5.5`\n- `Linux 5.9`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}