{"id":"CVE-2026-64327","summary":"usb: gadget: f_fs: Initialize epfile-\u003ein early to fix endpoint direction checks","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_fs: Initialize epfile-\u003ein early to fix endpoint direction checks\n\nWhen parsing endpoint descriptors, ffs_data_got_descs() generates the\neps_addrmap which contains the endpoint direction. However, epfile-\u003ein\nwas previously only populated in ffs_func_eps_enable() which executes\nupon USB host connection. As a result, early userspace ioctls like\nFUNCTIONFS_DMABUF_ATTACH that run before the host connects would see\nepfile-\u003ein as 0, leading to incorrect DMA directions.\n\nBy moving the initialization to ffs_epfiles_create(), epfile-\u003ein is\naccurate before userspace opens the endpoint files.","modified":"2026-07-27T04:03:21.407564106Z","published":"2026-07-25T08:49:55.426Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64327.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/82cf1142e5ccf2b6d6d22ef713aaf3e5f2b5716b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/82cfd4739011bdc7e87b5d585703427e89ddfaa5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9e04055ab5fc0470a0031ee6934739f9aa8f34a5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f99f32ea9aa976afcbec20647ed33b50a52002c1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64327.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64327"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"7b07a2a7ca02a20124b552be96c5a56910795488"},{"fixed":"82cf1142e5ccf2b6d6d22ef713aaf3e5f2b5716b"},{"fixed":"9e04055ab5fc0470a0031ee6934739f9aa8f34a5"},{"fixed":"f99f32ea9aa976afcbec20647ed33b50a52002c1"},{"fixed":"82cfd4739011bdc7e87b5d585703427e89ddfaa5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64327.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.9.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64327.json"}}],"schema_version":"1.7.5"}