CVE-2026-93137
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix use-after-free on mm_struct in bpf_find_vma() bpf_find_vma() reads task->mm and calls mmap_read_trylock(mm) without holding a reference on the mm. On a foreign task, a concurrent exit_mm() can free the mm_struct between the lockless read and the trylock, resulting in a use-after-free. mm_struct is not SLAB_TYPESAFE_BY_RCU. For the current task, task->mm is stable. For a foreign task, pin the mm under task->alloc_lock and release it with mmput_async(), mirroring commit d8e27d2d22b6 ("bpf: fix mm lifecycle in open-coded task_vma iterator"). Use spin_trylock() instead of get_task_mm() so BPF context does not block on alloc_lock. Reject irqs-disabled contexts and !CONFIG_MMU on the foreign-task path because dropping the mm reference is not safe there. Race: CPU0 (BPF program) CPU1 (exiting task) ============================ ========================== bpf_find_vma(foreign_task): mm = task->mm exit_mm(): task->mm = NULL mmput(mm) -> frees mm_struct mmap_read_trylock(mm) // UAF on mm
View original CVE JSON
{
"id": "CVE-2026-93137",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-17T17:18:08.600",
"lastModified": "2026-10-19T10:17:03.707",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix use-after-free on mm_struct in bpf_find_vma()\n\nbpf_find_vma() reads task->mm and calls mmap_read_trylock(mm) without\nholding a reference on the mm. On a foreign task, a concurrent exit_mm()\ncan free the mm_struct between the lockless read and the trylock,\nresulting in a use-after-free. mm_struct is not SLAB_TYPESAFE_BY_RCU.\n\nFor the current task, task->mm is stable. For a foreign task, pin the mm\nunder task->alloc_lock and release it with mmput_async(), mirroring commit\nd8e27d2d22b6 (\"bpf: fix mm lifecycle in open-coded task_vma iterator\").\nUse spin_trylock() instead of get_task_mm() so BPF context does not block\non alloc_lock. Reject irqs-disabled contexts and !CONFIG_MMU on the\nforeign-task path because dropping the mm reference is not safe there.\n\nRace:\n\n CPU0 (BPF program) CPU1 (exiting task)\n ============================ ==========================\n bpf_find_vma(foreign_task):\n mm = task->mm\n exit_mm():\n task->mm = NULL\n mmput(mm) -> frees mm_struct\n mmap_read_trylock(mm)\n // UAF on mm"
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/bpf/task_iter.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "7c7e3d31e7856a8260a254f8c71db416f7f9f5a1",
"lessThan": "db347840d6b6ee9bb9b8e4a985d4b4419f9f3200",
"versionType": "git",
"status": "affected"
},
{
"version": "7c7e3d31e7856a8260a254f8c71db416f7f9f5a1",
"lessThan": "8e1101fc4118019a69c96ced4aec93164f89cbd5",
"versionType": "git",
"status": "affected"
},
{
"version": "7c7e3d31e7856a8260a254f8c71db416f7f9f5a1",
"lessThan": "c7ad910e987008e125eeff448892e86852173384",
"versionType": "git",
"status": "affected"
},
{
"version": "7c7e3d31e7856a8260a254f8c71db416f7f9f5a1",
"lessThan": "86d54cf069fc5ae2e111c87933bebf6eb527978e",
"versionType": "git",
"status": "affected"
},
{
"version": "7c7e3d31e7856a8260a254f8c71db416f7f9f5a1",
"lessThan": "2b2a903bee56d312539046d9defa8023eec94760",
"versionType": "git",
"status": "affected"
},
{
"version": "7c7e3d31e7856a8260a254f8c71db416f7f9f5a1",
"lessThan": "47b079e2117a2ee52e21f8b72935900c702fc0b5",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"kernel/bpf/task_iter.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.17",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.17",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.188",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.157",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.110",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.52",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.6",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"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",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/2b2a903bee56d312539046d9defa8023eec94760",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/47b079e2117a2ee52e21f8b72935900c702fc0b5",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/86d54cf069fc5ae2e111c87933bebf6eb527978e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8e1101fc4118019a69c96ced4aec93164f89cbd5",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/c7ad910e987008e125eeff448892e86852173384",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/db347840d6b6ee9bb9b8e4a985d4b4419f9f3200",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}