{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-43392",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-05-01T14:12:56.007Z",
        "datePublished": "2026-05-08T14:21:36.692Z",
        "dateUpdated": "2026-05-11T22:23:41.885Z"
    },
    "containers": {
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            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T22:23:41.885Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix starvation of scx_enable() under fair-class saturation\n\nDuring scx_enable(), the READY -> ENABLED task switching loop changes the\ncalling thread's sched_class from fair to ext. Since fair has higher\npriority than ext, saturating fair-class workloads can indefinitely starve\nthe enable thread, hanging the system. This was introduced when the enable\npath switched from preempt_disable() to scx_bypass() which doesn't protect\nagainst fair-class starvation. Note that the original preempt_disable()\nprotection wasn't complete either - in partial switch modes, the calling\nthread could still be starved after preempt_enable() as it may have been\nswitched to ext class.\n\nFix it by offloading the enable body to a dedicated system-wide RT\n(SCHED_FIFO) kthread which cannot be starved by either fair or ext class\ntasks. scx_enable() lazily creates the kthread on first use and passes the\nops pointer through a struct scx_enable_cmd containing the kthread_work,\nthen synchronously waits for completion.\n\nThe workfn runs on a different kthread from sch->helper (which runs\ndisable_work), so it can safely flush disable_work on the error path\nwithout deadlock."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/sched/ext.c"
                    ],
                    "versions": [
                        {
                            "version": "8c2090c504e998c8f34ec870bae71dafcc96a6e0",
                            "lessThan": "e0b14bf06393be137d3efb6a3b7cd5b4b9810a6b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8c2090c504e998c8f34ec870bae71dafcc96a6e0",
                            "lessThan": "c44198f25fdfecc0ec0fe366bf8a47fe17d8e229",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8c2090c504e998c8f34ec870bae71dafcc96a6e0",
                            "lessThan": "05ab9ec5dc24f234e0a2fecf3e6ff937c68f7d81",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8c2090c504e998c8f34ec870bae71dafcc96a6e0",
                            "lessThan": "b06ccbabe2506fd70b9167a644978b049150224a",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/sched/ext.c"
                    ],
                    "versions": [
                        {
                            "version": "6.12",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.12",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.78",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.20",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.9",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
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                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.12",
                                    "versionEndExcluding": "6.12.78"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.12",
                                    "versionEndExcluding": "6.18.20"
                                },
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                                    "versionStartIncluding": "6.12",
                                    "versionEndExcluding": "6.19.9"
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                    "versionEndExcluding": "7.0"
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            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/e0b14bf06393be137d3efb6a3b7cd5b4b9810a6b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/c44198f25fdfecc0ec0fe366bf8a47fe17d8e229"
                },
                {
                    "url": "https://git.kernel.org/stable/c/05ab9ec5dc24f234e0a2fecf3e6ff937c68f7d81"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b06ccbabe2506fd70b9167a644978b049150224a"
                }
            ],
            "title": "sched_ext: Fix starvation of scx_enable() under fair-class saturation",
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