Files
vuln-cve/data/2026/98xxx/CVE-2026-98466.json
T

180 lines
9.7 KiB
JSON

{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-98466",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2026-09-25T10:25:14.351Z",
"datePublished": "2026-10-18T15:15:18.414Z",
"dateUpdated": "2026-11-10T18:15:14.388Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-11-10T18:15:14.388Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Transfer the hyp stack pages out of the host stage-2\n\nfix_host_ownership() walks only the linear-map alias of each memblock\nregion, and the per-CPU hyp stack, mapped in the private VA range for\nits guard page, has none.\n\nWalk each stack's VA range with the same walker."
}
],
"metrics": [
{
"cvssV3_1": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
"baseScore": 8.2,
"baseSeverity": "HIGH"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The local `module_init(kvm_arm_init)` path reaches `init_hyp_mode()` → `kvm_hyp_init_protection()` → `do_pkvm_init()` → `handle___pkvm_init()` → `__pkvm_init()` → `__pkvm_init_finalise()` → patched `fix_host_ownership()`. Exploitation accesses the omitted stack pages through host direct-map aliases; no wire or guest message supplies causal data.\nAC:L - With `kvm-arm.mode=protected`, the omitted pages retain host-owned state, so `handle_host_mem_abort()` → `host_stage2_idmap()` deterministically installs `PKVM_HOST_MEM_PROT` RWX mappings. The attacker controls the stack access and a following HVC; no race or external condition is required.\nPR:H - `/dev/kvm` ioctls only cause EL2 to use the stack; they do not expose `kvm_arm_hyp_stack_base` or its PFN. Writing the kernel direct-map alias requires control of host EL1 through real host-administrative privilege, unavailable through user namespaces.\nUI:N - After pKVM initialization, the host attacker can access the retained direct-map alias and invoke an HVC or `KVM_RUN` to make EL2 use the corrupted stack. No action by another user is required.\nS:C - The missing `host_stage2_set_owner_locked(..., PKVM_ID_HYP)` operation lets the host EL1 authority access the protected EL2 stack, crossing the stage-2 boundary that isolates the hypervisor and protected VMs.\nC:H - The host can read live EL2 stack contents, including saved registers and pointers. Its simultaneous write access to stack control data can hijack EL2 execution and expose hypervisor or protected-VM memory.\nI:H - The host can overwrite the active stack used by `__host_exit()` and `handle_trap()`, including saved frame and return state. Control-flow corruption at EL2 can modify hypervisor ownership metadata and protected-VM memory.\nA:H - Corrupting the per-CPU stack consumed on every host-to-EL2 trap can produce invalid returns or hypervisor faults, crashing the hypervisor and consequently the host or its protected VMs."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"arch/arm64/kvm/hyp/nvhe/setup.c"
],
"versions": [
{
"version": "1a919b17ef012ca0572bae759c27e5ea02bfb47f",
"lessThan": "6c7b5eb6f7f424f5b82d0f9469a5f5adcdf4d973",
"status": "affected",
"versionType": "git"
},
{
"version": "1a919b17ef012ca0572bae759c27e5ea02bfb47f",
"lessThan": "e5dd2a91a7ae3a276e6d79806127e923936e241b",
"status": "affected",
"versionType": "git"
},
{
"version": "1a919b17ef012ca0572bae759c27e5ea02bfb47f",
"lessThan": "22df195bff84300a3f04813d6148765c77ac565a",
"status": "affected",
"versionType": "git"
},
{
"version": "1a919b17ef012ca0572bae759c27e5ea02bfb47f",
"lessThan": "3a8c562892b96f35bba1e00d5e455a15963bbb92",
"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/hyp/nvhe/setup.c"
],
"versions": [
{
"version": "5.19",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.19",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.12.117",
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.18.55",
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.2.9",
"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": "5.19",
"versionEndExcluding": "6.12.117"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.19",
"versionEndExcluding": "6.18.55"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.19",
"versionEndExcluding": "7.2.9"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.19",
"versionEndExcluding": "7.3"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/6c7b5eb6f7f424f5b82d0f9469a5f5adcdf4d973"
},
{
"url": "https://git.kernel.org/stable/c/e5dd2a91a7ae3a276e6d79806127e923936e241b"
},
{
"url": "https://git.kernel.org/stable/c/22df195bff84300a3f04813d6148765c77ac565a"
},
{
"url": "https://git.kernel.org/stable/c/3a8c562892b96f35bba1e00d5e455a15963bbb92"
}
],
"title": "KVM: arm64: Transfer the hyp stack pages out of the host stage-2",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
}
}