{"cve":"CVE-2024-26640","nvd":{"published":"2024-03-18T11:15:11.043","modified":"2026-08-04T11:16:51.957","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: add sanity checks to rx zerocopy\n\nTCP rx zerocopy intent is to map pages initially allocated\nfrom NIC drivers, not pages owned by a fs.\n\nThis patch adds to can_map_frag() these additional checks:\n\n- Page must not be a compound one.\n- page->mapping must be NULL.\n\nThis fixes the panic reported by ZhangPeng.\n\nsyzbot was able to loopback packets built with sendfile(),\nmapping pages owned by an ext4 file to TCP rx zerocopy.\n\nr3 = socket$inet_tcp(0x2, 0x1, 0x0)\nmmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0)\nr4 = socket$inet_tcp(0x2, 0x1, 0x0)\nbind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10)\nconnect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10)\nr5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\\x00',\n    0x181e42, 0x0)\nfallocate(r5, 0x0, 0x0, 0x85b8)\nsendfile(r4, r5, 0x0, 0x8ba0)\ngetsockopt$inet_tcp_TCP_ZEROCOPY_RECEIVE(r4, 0x6, 0x23,\n    &(0x7f00000001c0)={&(0x7f0000ffb000/0x3000)=nil, 0x3000, 0x0, 0x0, 0x0,\n    0x0, 0x0, 0x0, 0x0}, &(0x7f0000000440)=0x40)\nr6 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\\x00',\n    0x181e42, 0x0)","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/1b8adcc0e2c584fec778add7777fe28e20781e60","https://git.kernel.org/stable/c/577e4432f3ac810049cb7e6b71f4d96ec7c6e894","https://git.kernel.org/stable/c/718f446e60316bf606946f7f42367d691d21541e","https://git.kernel.org/stable/c/b383d4ea272fe5795877506dcce5aad1f6330e5e","https://git.kernel.org/stable/c/d15cc0f66884ef2bed28c7ccbb11c102aa3a0760"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:46:54.846886191+00:00"},"epss":{"cve":"CVE-2024-26640","score":0.00242,"percentile":0.1538,"date":"2026-10-31"},"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."]}