{"id":"CVE-2026-64259","title":"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 th…","summary":"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 th…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","published":"2026-07-25","updated":"2026-07-27","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64259","references":[{"url":"https://git.kernel.org/stable/c/1efd3d474fc0ba74dfd984249bca78807d739812","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a635f427d57e2012102ae4886b48d8955c59fb86","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e1711479e9068ea31b31353a702a51e639c3d059","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00157,"epssPercentile":0.05285,"ingestedAt":"2026-07-27T06:16:49.591Z","slug":"CVE-2026-64259","body":"## Overview\n\nIn 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}