CVE-2026-90003

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-90003", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.780Z", "datePublished": "2026-09-16T10:33:13.420Z", "dateUpdated": "2026-10-19T08:56:17.256Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:56:17.256Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfutex: Prevent rcuwait use-after-free during requeue PI\n\nOn PREEMPT_RT, FUTEX_CMP_REQUEUE_PI can trigger a KASAN report\n(slab-out-of-bounds) in futex_requeue_pi_complete() invocation of\nrcuwait_wake_up().\n\nThe futex_q used by futex_wait_requeue_pi() is allocated on the waiter's\nstack. An early wakeup can race with a PI requeue as follows:\n\n waiter requeue task\n ------ ------------\nfutex_wait_requeue_pi()\n futex_do_wait()\n schedule()\n futex_requeue\n futex_proxy_trylock_atomic()\n futex_requeue_pi_prepare()\n Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_IN_PROGRESS\n* timeout/ signal wakes waiter *\n futex_requeue_pi_wakeup_sync()\n Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_WAIT\n requeue_pi_wake_futex\n futex_requeue_pi_complete()\n cmpxchg Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_LOCKED\n rcuwait_wait_event()\n if (atomic_read(&q->requeue_state) != Q_REQUEUE_PI_WAIT)\n break /* no schedule() */\n\n /* q.pi_state->owner == current */\n futex_private_hash_put()\n /* return from syscall */\n rcuwait_wake_up(&q->requeue_wait)\n /* q is gone */\n\nfutex_requeue_pi_complete() publishes Q_REQUEUE_PI_LOCKED before\ncalling rcuwait_wake_up(). The waiter observes this state in\nrcuwait_wait_event() before invoking schedule() in rcuwait_wait_event().\nHere, the waiter is free leave the syscall before requeue task can\ncomplete the wake.\n\nTo address this race skip rcuwait_wake_up() in the Q_REQUEUE_PI_LOCKED\ncase.\nThis state is only published by requeue_pi_wake_futex(), which saves\nq->task before futex_requeue_pi_complete() and wakes the waiter via\nwake_up_state().\n\nThis wake is intended to wake the waiter from its futex_do_wait() sleep.\nIf the waiter is still sleeping there, it can not get into the\nQ_REQUEUE_PI_WAIT state (and require this removed wake).\nShould the waiter be woken up from futex_do_wait() by other means (as in\nthis example) and sleep in futex_requeue_pi_wakeup_sync() then the\nwake_up_state() from requeue_pi_wake_futex() will wake it, too.\nShould the waiter task terminate before wake_up_state() had a chance to\nwake the task then the task pointer does not become invalid because the\nfutex_hash_bucket::lock is held and the task pointer is RCU protected.\n\n[bigeasy: Updated comment and commit message]"}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The bug is reached only through the local futex(2) syscalls FUTEX_WAIT_REQUEUE_PI and FUTEX_CMP_REQUEUE_PI into kernel/futex/requeue.c; there is no network, Bluetooth, or physical-device path.\nAC:L - The attacker controls both sides of the race: a waiter thread using FUTEX_WAIT_REQUEUE_PI with an attacker-chosen timeout or signal, and a concurrent FUTEX_CMP_REQUEUE_PI from another thread, and can retry with CPU pinning until the waiter returns before rcuwait_wake_up() on PREEMPT_RT.\nPR:L - Any unprivileged local user can invoke futex() with FUTEX_WAIT_REQUEUE_PI and FUTEX_CMP_REQUEUE_PI; do_futex() and futex_requeue() perform no capability or credential checks, CONFIG_FUTEX_PI is default-y, and the path is reachable from containers without elevated privileges.\nUI:N - The attacker's own threads perform the wait, timeout or signal, and PI requeue; no victim action such as mounting a filesystem or opening a file is required.\nS:U - The use-after-free corrupts kernel memory (the waiter's stack-allocated futex_q and a type-confused task_struct) within the same kernel security authority; this is a standard local privilege-escalation issue, not a VM, IOMMU, or hypervisor escape.\nC:H - This is a use-after-free of the waiter's stack-allocated futex_q.requeue_wait; rcuwait_wake_up() reads a stale, attacker-refilled task_struct pointer and dereferences it in try_to_wake_up(), enabling arbitrary kernel-memory disclosure.\nI:H - The stale futex_q lives on the attacker's own kernel stack, which a following syscall can refill with controlled bytes, so rcuwait_wake_up() passes an attacker-chosen pointer into try_to_wake_up(), which writes task state and makes indirect scheduler calls, enabling privilege escalation.\nA:H - In the unexploited case, rcuwait_wake_up() dereferences a wild pointer from reused stack memory and causes a kernel oops or panic; any use-after-free of this kind is a High availability impact."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/futex/requeue.c"], "versions": [{"version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "lessThan": "220ee9e04ca3b7f014c000264aa6c884f036c86e", "status": "affected", "versionType": "git"}, {"version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "lessThan": "81aadbd09bf1dcd3238212f336ba699503557ae8", "status": "affected", "versionType": "git"}, {"version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "lessThan": "244f301759fd34b1dd0b4192ce44f8ef224e027d", "status": "affected", "versionType": "git"}, {"version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "lessThan": "7d1559126d86be6e4f6a85663dfbfe85caa47e37", "status": "affected", "versionType": "git"}, {"version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "lessThan": "e4a4ccfa470f910b747b3ee8d18670ed8ac8a236", "status": "affected", "versionType": "git"}, {"version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "lessThan": "a3b8d46fe401cba3a5c46dea610e6eb3dc15370e", "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/futex/requeue.c"], "versions": [{"version": "5.15", "status": "affected"}, {"version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.5", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.1.188"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.157"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.110"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.51"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.2.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/220ee9e04ca3b7f014c000264aa6c884f036c86e"}, {"url": "https://git.kernel.org/stable/c/81aadbd09bf1dcd3238212f336ba699503557ae8"}, {"url": "https://git.kernel.org/stable/c/244f301759fd34b1dd0b4192ce44f8ef224e027d"}, {"url": "https://git.kernel.org/stable/c/7d1559126d86be6e4f6a85663dfbfe85caa47e37"}, {"url": "https://git.kernel.org/stable/c/e4a4ccfa470f910b747b3ee8d18670ed8ac8a236"}, {"url": "https://git.kernel.org/stable/c/a3b8d46fe401cba3a5c46dea610e6eb3dc15370e"}], "title": "futex: Prevent rcuwait use-after-free during requeue PI", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/futex/requeue.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "220ee9e04ca3b7f014c000264aa6c884f036c86e", "status": "affected", "version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "versionType": "git"}, {"lessThan": "81aadbd09bf1dcd3238212f336ba699503557ae8", "status": "affected", "version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "versionType": "git"}, {"lessThan": "244f301759fd34b1dd0b4192ce44f8ef224e027d", "status": "affected", "version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "versionType": "git"}, {"lessThan": "7d1559126d86be6e4f6a85663dfbfe85caa47e37", "status": "affected", "version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "versionType": "git"}, {"lessThan": "e4a4ccfa470f910b747b3ee8d18670ed8ac8a236", "status": "affected", "version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "versionType": "git"}, {"lessThan": "a3b8d46fe401cba3a5c46dea610e6eb3dc15370e", "status": "affected", "version": "07d91ef510fb16a2e0ca7453222105835b7ba3b8", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/futex/requeue.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.15"}, {"lessThan": "5.15", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.188", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.157", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.110", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.51", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfutex: Prevent rcuwait use-after-free during requeue PI\n\nOn PREEMPT_RT, FUTEX_CMP_REQUEUE_PI can trigger a KASAN report\n(slab-out-of-bounds) in futex_requeue_pi_complete() invocation of\nrcuwait_wake_up().\n\nThe futex_q used by futex_wait_requeue_pi() is allocated on the waiter's\nstack. An early wakeup can race with a PI requeue as follows:\n\n waiter requeue task\n ------ ------------\nfutex_wait_requeue_pi()\n futex_do_wait()\n schedule()\n futex_requeue\n futex_proxy_trylock_atomic()\n futex_requeue_pi_prepare()\n Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_IN_PROGRESS\n* timeout/ signal wakes waiter *\n futex_requeue_pi_wakeup_sync()\n Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_WAIT\n requeue_pi_wake_futex\n futex_requeue_pi_complete()\n cmpxchg Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_LOCKED\n rcuwait_wait_event()\n if (atomic_read(&q->requeue_state) != Q_REQUEUE_PI_WAIT)\n break /* no schedule() */\n\n /* q.pi_state->owner == current */\n futex_private_hash_put()\n /* return from syscall */\n rcuwait_wake_up(&q->requeue_wait)\n /* q is gone */\n\nfutex_requeue_pi_complete() publishes Q_REQUEUE_PI_LOCKED before\ncalling rcuwait_wake_up(). The waiter observes this state in\nrcuwait_wait_event() before invoking schedule() in rcuwait_wait_event().\nHere, the waiter is free leave the syscall before requeue task can\ncomplete the wake.\n\nTo address this race skip rcuwait_wake_up() in the Q_REQUEUE_PI_LOCKED\ncase.\nThis state is only published by requeue_pi_wake_futex(), which saves\nq->task before futex_requeue_pi_complete() and wakes the waiter via\nwake_up_state().\n\nThis wake is intended to wake the waiter from its futex_do_wait() sleep.\nIf the waiter is still sleeping there, it can not get into the\nQ_REQUEUE_PI_WAIT state (and require this removed wake).\nShould the waiter be woken up from futex_do_wait() by other means (as in\nthis example) and sleep in futex_requeue_pi_wakeup_sync() then the\nwake_up_state() from requeue_pi_wake_futex() will wake it, too.\nShould the waiter task terminate before wake_up_state() had a chance to\nwake the task then the task pointer does not become invalid because the\nfutex_hash_bucket::lock is held and the task pointer is RCU protected.\n\n[bigeasy: Updated comment and commit message]"}], "id": "CVE-2026-90003", "lastModified": "2026-10-19T09:18:47.943", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-09-16T11:17:12.810", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/220ee9e04ca3b7f014c000264aa6c884f036c86e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/244f301759fd34b1dd0b4192ce44f8ef224e027d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7d1559126d86be6e4f6a85663dfbfe85caa47e37"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/81aadbd09bf1dcd3238212f336ba699503557ae8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a3b8d46fe401cba3a5c46dea610e6eb3dc15370e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e4a4ccfa470f910b747b3ee8d18670ed8ac8a236"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[07d91ef510fb16a2e0ca7453222105835b7ba3b8,220ee9e04ca3b7f014c000264aa6c884f036c86e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[07d91ef510fb16a2e0ca7453222105835b7ba3b8,81aadbd09bf1dcd3238212f336ba699503557ae8)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[07d91ef510fb16a2e0ca7453222105835b7ba3b8,244f301759fd34b1dd0b4192ce44f8ef224e027d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[07d91ef510fb16a2e0ca7453222105835b7ba3b8,7d1559126d86be6e4f6a85663dfbfe85caa47e37)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[07d91ef510fb16a2e0ca7453222105835b7ba3b8,e4a4ccfa470f910b747b3ee8d18670ed8ac8a236)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[07d91ef510fb16a2e0ca7453222105835b7ba3b8,a3b8d46fe401cba3a5c46dea610e6eb3dc15370e)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "5.15"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.15)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1188,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.157,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.110,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.51,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.5,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc2,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-18T05:00:03.714508+00:00", "updated": "2026-09-18T07:45:05.211474+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-416"]}