{"cve":"CVE-2026-80859","nvd":{"published":"2026-09-04T16:18:15.070","modified":"2026-10-19T09:17:21.583","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfuse: fix missing barrier when checking io-uring readiness\n\nfuse_block_alloc() reads fch->initialized and then fch->io_uring.\nfch->io_uring is set before fch->initialized, ordered by the smp_wmb()\nin fuse_chan_set_intialized(), but fuse_block_alloc() has no matching\nread barrier between the two loads.\n\nThis may lead a CPU to observe fch->initialized=1 but fch->io_uring=0,\nand skip the check that blocks request allocation until the io-uring\nqueues are ready. This can reintroduce the lock-order inversion deadlock\nthat commit 3393ff964e0f prevents.\n\nAdd an smp_rmb() barrier to pair with the smp_wmb() in\nfuse_chan_set_initialized() to prevent this.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/8974575898cd7a4c818088f102b2e7a0286d3302","https://git.kernel.org/stable/c/dd9c835709f4bb3e4256eea7573e4e6e18f956de","https://git.kernel.org/stable/c/edb310bc27f0ad83e7fd558a3caf1a94ca511654"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:52:03.409947763+00:00"},"epss":{"cve":"CVE-2026-80859","score":0.00155,"percentile":0.0454,"date":"2026-10-25"},"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."]}