{"cve":"CVE-2026-90051","nvd":{"published":"2026-09-17T17:16:53.490","modified":"2026-10-19T09:18:53.417","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: reject non zerocopy devmem tx\n\nDevmem tcp tx doesn't work without zero-copy, however it's not currently\nenforced if NETIF_F_SG isn't present. In this case, tcp_sendmsg_locked()\nwill try the copy path and try to copy data from an iovec which consists\nof offsets into the dma-buf and would normally fail. Moreover,\nd9c56501c72fd (\"net: tcp: block mixing readable and unreadable frags\")\nrelies on that and assumes that the devmem binding is present IFF we're\nusing the zero-copy path, which can be used to mix net-iov and pages in\na single skb, and break invariants. Let's reject devmem tx without\nzero-copy.\n\nNote, the parameter check the patch is modifying is too loose, we can\ncreate an io_uring request with dmabuf_id and all ZC flags, but which\nwon't have the binding. We replace it with stricter validation.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/125755776bc6d4dd53eaf551c87e3d460625d638","https://git.kernel.org/stable/c/2151b2bcf6fcec52665f606eed20da068447f0b7","https://git.kernel.org/stable/c/b04326c7927af7048fd4e730f5770cca350d0a60"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90051","score":0.00162,"percentile":0.05295,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}