197 lines
13 KiB
JSON
197 lines
13 KiB
JSON
{
|
|
"dataType": "CVE_RECORD",
|
|
"dataVersion": "5.2",
|
|
"cveMetadata": {
|
|
"cveId": "CVE-2026-74568",
|
|
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"state": "PUBLISHED",
|
|
"assignerShortName": "Linux",
|
|
"dateReserved": "2026-08-15T05:44:03.917Z",
|
|
"datePublished": "2026-08-15T12:28:08.859Z",
|
|
"dateUpdated": "2026-10-16T19:05:56.525Z"
|
|
},
|
|
"containers": {
|
|
"cna": {
|
|
"providerMetadata": {
|
|
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"shortName": "Linux",
|
|
"dateUpdated": "2026-10-15T10:09:17.216Z"
|
|
},
|
|
"descriptions": [
|
|
{
|
|
"lang": "en",
|
|
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: vgic: Fix race between LPI release and re-registration\n\nFix a potential race between decrementing an LPI's reference count and\nevicting that structure from the LPI xarray.\n\nLPI structures are maintained in the VGIC LPI xarray (dist->lpi_xa).\nWhen the reference count of an LPI structure drops to zero,\nvgic_release_lpi_locked() removes the structure from the xarray and\nfrees it under the xarray lock.\n\nHowever, the release of an LPI can race with a concurrent LPI\nre-registration with the same INTID via vgic_add_lpi() on another CPU,\nsince the reference count drop and the xarray eviction are not performed\nin a single atomic step. This can happen e.g. if the guest issues a\nDISCARD while the LPI is still referenced from a vCPU's active-pending\nlist (ap_list), and the same INTID is re-mapped via MAPTI.\n\nParticularly, vgic_release_lpi_locked() is called from two distinct\npaths: direct release via vgic_put_irq(), and deferred release via\nvgic_release_deleted_lpis(). During direct release, the issue can result\nin deleting a newly registered LPI from the xarray:\n\n CPU0 (Releasing LPI) CPU1 (Adding new LPI)\n ==================== =====================\n vgic_put_irq()\n __vgic_put_irq()\n refcount_dec_and_test()\n vgic_add_lpi()\n xa_lock_irqsave()\n old_irq = xa_load(.., intid)\n vgic_try_get_irq_ref(old_irq) == false\n new IRQ inserted --> __xa_store(.., intid, ..)\n xa_unlock_irqrestore()\n xa_lock_irqsave();\n vgic_release_lpi_locked()\n __xa_erase(.., irq->intid) <-- BUG: new IRQ is erased\n kfree_rcu(old_irq)\n\nDuring the deferred release path, the old IRQ can be leaked:\n\n CPU0 (Releasing LPI) CPU1 (Adding new LPI)\n ==================== =====================\n vgic_put_irq_norelease()\n __vgic_put_irq()\n refcount_dec_and_test()\n irq->pending_release = true\n vgic_add_lpi()\n xa_lock_irqsave()\n old_irq = xa_load(.., intid)\n vgic_try_get_irq_ref(oldirq) == false\n BUG: old IRQ overwritten --> __xa_store(.., intid, ..)\n xa_unlock_irqrestore()\n\n vgic_release_deleted_lpis()\n xa_lock_irqsave()\n xa_for_each() { .. } <-- old IRQ with pending_release = true\n is gone, so it cannot be released\n\nTo fix the direct release path, move the reference count drop inside\nthe xarray lock, making sure that vgic_add_lpi() never encounters the\nto-be-released LPI.\n\nIn the deferred release path, the refcount drop must happen under a raw\nspinlock, so the xarray lock cannot be grabbed, and the same solution\ndoes not work. Instead, update vgic_add_lpi(), so that if it evicts\nan LPI from the xarray, it takes on the responsibility of freeing it.\nConsequently, an LPI may now be freed concurrently after a deferred\nrelease drops the refcount, so accessing the pending_release field is no\nlonger safe from use-after-free. Delete all uses of the flag, and update\nvgic_release_deleted_lpis() to identify orphaned LPIs purely based on\ntheir refcount."
|
|
}
|
|
],
|
|
"metrics": [
|
|
{
|
|
"cvssV3_1": {
|
|
"version": "3.1",
|
|
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
|
|
"baseScore": 9.3,
|
|
"baseSeverity": "CRITICAL"
|
|
},
|
|
"scenarios": [
|
|
{
|
|
"lang": "en",
|
|
"value": "AV:L - The bug is reached when a malicious KVM guest writes emulated GICv3 ITS MMIO (GITS_CWRITER), processing DISCARD/MAPTI commands that call vgic_add_lpi() and vgic_put_irq(); this requires guest code execution on the host, not remote network input.\nAC:L - The race is guest-driven and repeatable: a malicious guest can keep an LPI referenced on a vCPU ap_list, issue DISCARD, and concurrently re-map the same INTID via MAPTI across vCPUs, controlling both sides of the refcount/xarray race.\nPR:N - Exploitation requires only code inside a KVM guest on an arm64 host with VGICv3 ITS/LPI (common on cloud ARM servers); no host root, CAP_SYS_ADMIN, or other elevated host privileges are needed beyond normal VM tenancy.\nUI:N - No victim interaction is required; the attacker fully controls guest ITS command submission, interrupt injection, and multi-vCPU timing from within the VM.\nS:C - Corrupting host-kernel VGIC LPI objects (lpi_xa entries, vgic_irq structures) from guest MMIO crosses the KVM virtual-machine security boundary and can enable guest-to-host escape.\nC:H - The race can erase a newly registered LPI while freeing the old one, leaving stale host pointers (ite->irq, ap_list) to freed vgic_irq objects; this use-after-free enables arbitrary host kernel memory disclosure via heap reuse.\nI:H - Host heap corruption of vgic_irq structures and xarray state from the race provides use-after-free write primitives that can be leveraged for arbitrary host kernel modification and VM escape code execution.\nA:H - The bug can cause host kernel crashes (oops/panic) from freeing live LPIs, orphaned IRQ state, and use-after-free during concurrent VGIC interrupt handling on multiple vCPUs."
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"affected": [
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "unaffected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"arch/arm64/kvm/vgic/vgic-its.c",
|
|
"arch/arm64/kvm/vgic/vgic.c",
|
|
"include/kvm/arm_vgic.h"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a",
|
|
"lessThan": "f8e5715a37378ea1a140ee1162fa441e149c5142",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a",
|
|
"lessThan": "292e80a159aa88635bf668a7212cfdf526b8bd52",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a",
|
|
"lessThan": "cbfe2b24a1ea9de35032dbdd100fdc700f5be92d",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
}
|
|
]
|
|
},
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "affected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"arch/arm64/kvm/vgic/vgic-its.c",
|
|
"arch/arm64/kvm/vgic/vgic.c",
|
|
"include/kvm/arm_vgic.h"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "6.17",
|
|
"status": "affected"
|
|
},
|
|
{
|
|
"version": "0",
|
|
"lessThan": "6.17",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.18.57",
|
|
"lessThanOrEqual": "6.18.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "7.1.8",
|
|
"lessThanOrEqual": "7.1.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "7.2",
|
|
"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": "6.17",
|
|
"versionEndExcluding": "6.18.57"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.17",
|
|
"versionEndExcluding": "7.1.8"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.17",
|
|
"versionEndExcluding": "7.2"
|
|
}
|
|
]
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"references": [
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/f8e5715a37378ea1a140ee1162fa441e149c5142"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/292e80a159aa88635bf668a7212cfdf526b8bd52"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/cbfe2b24a1ea9de35032dbdd100fdc700f5be92d"
|
|
}
|
|
],
|
|
"title": "KVM: arm64: vgic: Fix race between LPI release and re-registration",
|
|
"x_generator": {
|
|
"engine": "bippy-1.2.0"
|
|
}
|
|
},
|
|
"adp": [
|
|
{
|
|
"metrics": [
|
|
{
|
|
"other": {
|
|
"type": "ssvc",
|
|
"content": {
|
|
"id": "CVE-2026-74568",
|
|
"role": "CISA Coordinator",
|
|
"options": [
|
|
{
|
|
"Exploitation": "none"
|
|
},
|
|
{
|
|
"Automatable": "no"
|
|
},
|
|
{
|
|
"Technical Impact": "total"
|
|
}
|
|
],
|
|
"version": "2.0.3",
|
|
"timestamp": "2026-10-16T19:00:27.387340Z"
|
|
}
|
|
}
|
|
}
|
|
],
|
|
"title": "CISA ADP Vulnrichment",
|
|
"providerMetadata": {
|
|
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
|
|
"shortName": "CISA-ADP",
|
|
"dateUpdated": "2026-10-16T19:05:56.525Z"
|
|
}
|
|
}
|
|
]
|
|
}
|
|
} |