CVE-2026-31734

{"id": "CVE-2026-31734", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "8e4f0b1ebcf2180ab594f204f01279a666dadf3b", "lessThan": "72c43eb2e334febe93018cfb68ae828f55c6e49e", "versionType": "git"}, {"status": "affected", "version": "8e4f0b1ebcf2180ab594f204f01279a666dadf3b", "lessThan": "b4992a9446bb9a639007bfd32bf5c5a7e30199e5", "versionType": "git"}, {"status": "affected", "version": "8e4f0b1ebcf2180ab594f204f01279a666dadf3b", "lessThan": "0c4a59df370bea245695c00aaae6ae75747139bd", "versionType": "git"}], "programFiles": ["kernel/sched/ext_idle.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.18"}, {"status": "unaffected", "version": "0", "lessThan": "6.18", "versionType": "semver"}, {"status": "unaffected", "version": "6.18.22", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "6.19.12", "versionType": "semver", "lessThanOrEqual": "6.19.*"}, {"status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["kernel/sched/ext_idle.c"], "defaultStatus": "affected"}]}], "published": "2026-05-01T15:16:36.030", "references": [{"url": "https://git.kernel.org/stable/c/0c4a59df370bea245695c00aaae6ae75747139bd", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/72c43eb2e334febe93018cfb68ae828f55c6e49e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b4992a9446bb9a639007bfd32bf5c5a7e30199e5", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix is_bpf_migration_disabled() false negative on non-PREEMPT_RCU\n\nSince commit 8e4f0b1ebcf2 (\"bpf: use rcu_read_lock_dont_migrate() for\ntrampoline.c\"), the BPF prolog (__bpf_prog_enter) calls migrate_disable()\nonly when CONFIG_PREEMPT_RCU is enabled, via rcu_read_lock_dont_migrate().\nWithout CONFIG_PREEMPT_RCU, the prolog never touches migration_disabled,\nso migration_disabled == 1 always means the task is truly\nmigration-disabled regardless of whether it is the current task.\n\nThe old unconditional p == current check was a false negative in this\ncase, potentially allowing a migration-disabled task to be dispatched to\na remote CPU and triggering scx_error in task_can_run_on_remote_rq().\n\nOnly apply the p == current disambiguation when CONFIG_PREEMPT_RCU is\nenabled, where the ambiguity with the BPF prolog still exists."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nsched_ext: Soluci\u00f3n de falso negativo en is_bpf_migration_disabled() en no-PREEMPT_RCU\n\nDesde el commit 8e4f0b1ebcf2 (\u2019bpf: usar rcu_read_lock_dont_migrate() para trampoline.c\u2019), el pr\u00f3logo BPF (__bpf_prog_enter) llama a migrate_disable() solo cuando CONFIG_PREEMPT_RCU est\u00e1 habilitado, a trav\u00e9s de rcu_read_lock_dont_migrate(). Sin CONFIG_PREEMPT_RCU, el pr\u00f3logo nunca toca migration_disabled, por lo que migration_disabled == 1 siempre significa que la tarea tiene la migraci\u00f3n verdaderamente deshabilitada, independientemente de si es la tarea actual.\n\nLa antigua comprobaci\u00f3n incondicional p == current era un falso negativo en este caso, lo que potencialmente permit\u00eda que una tarea con la migraci\u00f3n deshabilitada fuera despachada a una CPU remota y desencadenando scx_error en task_can_run_on_remote_rq().\n\nSolo aplicar la desambiguaci\u00f3n p == current cuando CONFIG_PREEMPT_RCU est\u00e1 habilitado, donde la ambig\u00fcedad con el pr\u00f3logo BPF a\u00fan existe."}], "lastModified": "2026-11-11T21:10:00.200", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BFDF75B5-A823-4448-88D3-3029C0464168", "versionEndExcluding": "6.18.22", "versionStartIncluding": "6.18"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0A2B9540-02D5-41B4-B16A-82AF66FD4F36", "versionEndExcluding": "6.19.12", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}