CVE-2026-64291
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: iommufd: Set veventq_depth upper bound iommufd_veventq_alloc() accepts any !0 veventq_depth from userspace, with an upper bound at U32_MAX. This leaves a vulnerability where userspace can allocate excessively large queues to exhaust kernel memory reserves. Cap the veventq_depth (maximum number of entries) to 1 << 19, matching the maximum number of entries in the SMMUv3 EVTQ (the largest use case today).
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:09.837000
Last modified
2026-11-06 17:18:45.850000
View original CVE JSON
{
"id": "CVE-2026-64291",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-07-25T10:17:09.837",
"lastModified": "2026-11-06T17:18:45.850",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommufd: Set veventq_depth upper bound\n\niommufd_veventq_alloc() accepts any !0 veventq_depth from userspace, with\nan upper bound at U32_MAX.\n\nThis leaves a vulnerability where userspace can allocate excessively large\nqueues to exhaust kernel memory reserves.\n\nCap the veventq_depth (maximum number of entries) to 1 << 19, matching the\nmaximum number of entries in the SMMUv3 EVTQ (the largest use case today)."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/iommu/iommufd/eventq.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "e36ba5ab808ef6237c3148d469c8238674230e2b",
"lessThan": "f565297edf316016be4a1a9e2eb9f39359313f43",
"versionType": "git",
"status": "affected"
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{
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"programFiles": [
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],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
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{
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"versionType": "semver",
"status": "unaffected"
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{
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{
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"versionType": "original_commit_for_fix",
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}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-11-06T16:34:03.370926Z",
"id": "CVE-2026-64291",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
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}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
]
}
],
"configurations": [
{
"nodes": [
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"operator": "OR",
"negate": false,
"cpeMatch": [
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"matchCriteriaId": "1DA3E752-10DF-4260-A04E-FB6A07086768"
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"references": [
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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}