{"cve":"CVE-2026-89520","nvd":{"published":"2026-09-11T20:19:34.647","modified":"2026-10-21T13:20:06.543","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/core: Make core-sched flips wait for in-flight selections\n\nCore scheduling's pick_next_task() operates on all sibling rqs under one\nacquisition of the shared core-wide lock. A ->pick_task() that releases the\nrq lock leaves every sibling __lock momentarily free, letting\n__sched_core_flip(false) complete mid-selection and rebind rq_lockp() under\nit. The selection resumes on the split locks, touching sibling state it no\nlonger protects, and __schedule() finally releases a lock that was never\ntaken while leaking the one that was.\n\nCount in-flight core-wide selections in the leader's rq->core_pick_in_flight\nand make __sched_core_flip() wait for the count to drain. The count only\nchanges under the shared lock, which the flip holds while sampling, so no\nother ordering is needed. The wait can repeat while selections overlap, but\nthe flip backs off between samples and flips are rare cookie-lifetime\nevents.\n\nsched_core_cpu_deactivate() moves the count to the new leader - a stale copy\nleft behind would bias it forever if that CPU later returns as its own\nleader.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/23eda24f325a6e6d686d30ec75f2e9d6745e2015","https://git.kernel.org/stable/c/3e2511bffa93a639774a99e392181e21d28677e2","https://git.kernel.org/stable/c/9d69422ddaa13526c2223444e237d948d6e44728","https://git.kernel.org/stable/c/a2a16896ed53046f275f56a6cd8ca3fb6f12c4f3","https://git.kernel.org/stable/c/f3629c63a4af3e491381780bc6c123cb498c4c40"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-89520","score":0.00168,"percentile":0.0617,"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."]}