{"cve":"CVE-2026-53328","nvd":{"published":"2026-07-01T14:16:40.650","modified":"2026-07-23T20:52:41.010","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Don't warn on NULL cgrp_moving_from in scx_cgroup_move_task()\n\nA WARN fires when systemd's user manager writes \"+cpu +memory +pids\" to\nits own subtree_control while a sched_ext scheduler is loaded:\n\n  WARNING: at kernel/sched/ext.c:3227 scx_cgroup_move_task+0xa8/0xb0\n   scx_cgroup_move_task+0xa8/0xb0\n   sched_move_task+0x134/0x290\n   cpu_cgroup_attach+0x39/0x70\n   cgroup_migrate_execute+0x37d/0x450\n   cgroup_update_dfl_csses+0x1e3/0x270\n   cgroup_subtree_control_write+0x3e7/0x440\n\nscx_cgroup_can_attach() arms cgrp_moving_from only when a task's cpu\ncgroup changes. It can still be NULL when scx_cgroup_move_task() runs,\nthrough this sequence:\n\n  Step                               Result\n  ---------------------------------  ----------------------------------\n  1. cpu enabled on cgroup G         cpu css = A\n  2. cpu toggled off then on for G   A killed, B created (same cgroup)\n  3. an exiting task keeps A alive   migration skips it, A now stale\n  4. +memory migrates G              stale A vs current B pulls cpu in\n  5. cpu attach runs for all tasks   hits a live, cpu-unchanged task\n  6. scx_cgroup_move_task() on it    cgrp_moving_from NULL -> WARN\n\nThe mismatch is that scx_cgroup_can_attach() keys on cgroup identity\nwhile migration drives the move on css identity, so a NULL cgrp_moving_from\nhere is a legitimate css-only migration, not a missing prep.\n\nThe call is already gated on cgrp_moving_from, so just drop the warning.\nops.cgroup_prep_move() and ops.cgroup_move() stay paired.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/02e545c4297a26dbbc41df81b831e7f605bcd306","https://git.kernel.org/stable/c/0ffcad63b19a1cadb475c9f405a93607fdcd0d7c","https://git.kernel.org/stable/c/bc75f5951fac4e49d175c4433fc08fb1ec01172f","https://git.kernel.org/stable/c/cdff2eb97be147d2ce52ac1327841068781f25dc"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:42:16.820116992+00:00"},"epss":{"cve":"CVE-2026-53328","score":0.00162,"percentile":0.05346,"date":"2026-10-31"},"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."]}