{"id":"CVE-2026-64259","summary":"fuse-uring: make a fuse_req on SQE commit only findable after memcpy","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: make a fuse_req on SQE commit only findable after memcpy\n\nBad userspace might try to trick us and send commit SQEs request\nunique / commit-id of requests that are not even send to\nfuse-server (io_uring_cmd_done() not called) yet.\n\nfuse_uring_commit_fetch() ends the fuse request when the ring entry\nhas a wrong state, but that could have caused a use-after-free\nwith the memcpy operations in fuse_uring_send_in_task().\nIn order to avoid such races the call of fuse_uring_add_to_pq()\nis moved after the copy operations and just before completing\nthe io-uring request - malicious userspace cannot find the request\nanymore until all prepration work in fuse-client/kernel is completed.\n\nThis also moves fuse_uring_add_to_pq() a bit up in the code to\navoid a forward declaration. Also not with a preparation commit,\nto make it easier to back port to older kernels.","modified":"2026-07-28T04:02:28.152726738Z","published":"2026-07-25T08:49:10.756Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64259.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1efd3d474fc0ba74dfd984249bca78807d739812"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a635f427d57e2012102ae4886b48d8955c59fb86"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e1711479e9068ea31b31353a702a51e639c3d059"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64259.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64259"},{"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":"c090c8abae4b6b77a1bee116aa6c385456ebef96"},{"fixed":"e1711479e9068ea31b31353a702a51e639c3d059"},{"fixed":"a635f427d57e2012102ae4886b48d8955c59fb86"},{"fixed":"1efd3d474fc0ba74dfd984249bca78807d739812"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64259.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.14.0"},{"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-2026-64259.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}