{"id":"CVE-2026-64588","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: fix data races on ring->ready\n\nOn weakly-ordered architectures, the store to fiq->ops can be\nreordered past the store to ring->ready, allowing a CPU that se…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: fix data races on ring->ready\n\nOn weakly-ordered architectures, the store to fiq->ops can be\nreordered past the store to ring->ready, allowing a CPU that se…","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":"2026-08-06","updated":"2026-08-08","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64588","references":[{"url":"https://git.kernel.org/stable/c/46725a0056c884cf58a6897f222892807327d82d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b156bb9966972122b148acab8bdf415cdb8176a3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d01a09b442cb786cd44ccc7c84d57e2856d6737c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00119,"epssPercentile":0.01988,"ingestedAt":"2026-08-08T21:30:13.260Z","slug":"CVE-2026-64588","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: fix data races on ring->ready\n\nOn weakly-ordered architectures, the store to fiq->ops can be\nreordered past the store to ring->ready, allowing a CPU that sees\nring->ready == true via fuse_uring_ready() to dispatch requests\nthrough a stale fiq->ops pointer. Upgrade the store to\nsmp_store_release() and the load in fuse_uring_ready() to\nsmp_load_acquire() so that the preceding WRITE_ONCE(fiq->ops, ...)\nis visible to any CPU that observes ring->ready == true.\n\nAdditionally, fuse_uring_do_register() publishes ring->ready with\nWRITE_ONCE() but the fast-path check reads it with a plain load.\nThis is a marked-vs-unmarked access that KCSAN will flag. Wrap it in\nREAD_ONCE() to mark it without adding unnecessary ordering.\n\nAlso wrap the fc->ring load in fuse_uring_ready() in READ_ONCE() to\nprevent the compiler from reloading it between the NULL check and the\ndereference.\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":[]}