{"id":"CVE-2026-89519","title":"sched_ext: Replace SCX_RQ_BAL_KEEP with a dispatch verdict return","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Replace SCX_RQ_BAL_KEEP with a dispatch verdict return\n\nSCX_RQ_BAL_KEEP tells the pick to keep running the previous task, a leftover\nfrom when balancing and …","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":["CWE-367"],"vendor":"Linux","product":"Linux","affected":["Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < 6f1d3bfe54430f8d54e0530a27f2ecbf8466576e","Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < ffaab58d217581cb75353168f8812a16e10463fc","Linux 6.19"],"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:48:10.533Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89519","references":[{"url":"https://git.kernel.org/stable/c/6f1d3bfe54430f8d54e0530a27f2ecbf8466576e"},{"url":"https://git.kernel.org/stable/c/ffaab58d217581cb75353168f8812a16e10463fc"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89519.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89519"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532339"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89519"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89519"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89519.mbox"}],"tags":["cve.org","csaf","vex","red-hat"],"epss":0.00198,"epssPercentile":0.09434,"ingestedAt":"2026-09-14T11:11:19.886Z","slug":"CVE-2026-89519","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Replace SCX_RQ_BAL_KEEP with a dispatch verdict return\n\nSCX_RQ_BAL_KEEP tells the pick to keep running the previous task, a leftover\nfrom when balancing and picking were separate operations. An rq-level flag\nonly works while dispatches and picks pair up one to one, which core\nscheduling breaks: selections interleave through dispatch's lock drops and a\npick can consume a stale flag, keeping a task that has since been dequeued.\nFixing core scheduling support requires the decision to travel with the\ndispatch that made it. Make scx_dispatch_sched() and balance_one() return an\nexplicit verdict instead and drop the flag's plumbing from the tools autogen\nenum headers.\n\nAlso factor the pick-side invocation, its follow-up queueing and the\npost-dispatch checks out of do_pick_task_scx() into dispatch_pick(). No\nfunctional changes intended.\n\nv2: Drop the SCX_RQ_BAL_KEEP plumbing from the tools autogen enum headers\n    as well (Andrea).\n\n## Affected\n\n- `Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < 6f1d3bfe54430f8d54e0530a27f2ecbf8466576e`\n- `Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < ffaab58d217581cb75353168f8812a16e10463fc`\n- `Linux 6.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89519.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":203994,"id":"CVE-2026-89519","ts":1789490230961,"field":"cvss","old":null,"new":"5.5"},{"seq":203993,"id":"CVE-2026-89519","ts":1789490230961,"field":"severity","old":"none","new":"medium"},{"seq":147355,"id":"CVE-2026-89519","ts":1789270210581,"field":"cvss","old":null,"new":"5.5"},{"seq":147354,"id":"CVE-2026-89519","ts":1789270210581,"field":"severity","old":"none","new":"medium"},{"seq":109108,"id":"CVE-2026-89519","ts":1789183730334,"field":"cvss","old":null,"new":"5.5"},{"seq":109107,"id":"CVE-2026-89519","ts":1789183730334,"field":"severity","old":"none","new":"medium"}]}