CVE-2026-64307 (GCVE-0-2026-64307)
Vulnerability from cvelistv5
Published
2026-07-25 08:49
Modified
2026-08-17 04:53
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)
Sashiko notes:
> if SEV initialization fails and KVM is actively running normal VMs, could a
> userspace process trigger this code path via /dev/sev ioctls (e.g.,
> SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN
> execution for an active VM trigger a general protection fault and crash the
> host?
Refuse to re-try initialization if SNP is not already initialized for
SNP_CONFIG.
This is technically an ABI break: before if SNP initialization failed it
could be transparently retriggered by this ioctl, and if no VMs were
running, everything worked fine. Hopefully this is enough of a corner case
that nobody will notice, but someone does, there are a few options:
* do something like symbol_get() for kvm and refuse to initialize if KVM is
loaded
* check each cpu's HSAVE_PA for non-zero data before re-initializing
* once initialization has failed, continue to refuse to initialize until
the ccp module is unloaded
References
| URL | Tags | |
|---|---|---|
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/crypto/ccp/sev-dev.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "345a6e869b33687e9268044bcaeeefd7c61da675",
"status": "affected",
"version": "1c3506ea8599a3ad1b9aae5cbd573134f8d18db7",
"versionType": "git"
},
{
"lessThan": "441ea32cf2755a0dc593557056b00b7caa0651f5",
"status": "affected",
"version": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c",
"versionType": "git"
},
{
"lessThan": "20f548cdac94860a164e5ebba4f7e4a01051cb06",
"status": "affected",
"version": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c",
"versionType": "git"
},
{
"lessThan": "08f0e65e784c4b20e6e620dd4f68d8636073a3d2",
"status": "affected",
"version": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c",
"versionType": "git"
},
{
"lessThan": "6.12.97",
"status": "affected",
"version": "6.12.75",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/crypto/ccp/sev-dev.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.16"
},
{
"lessThan": "6.16",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.4",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.97",
"versionStartIncluding": "6.12.75",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.39",
"versionStartIncluding": "6.16",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.4",
"versionStartIncluding": "6.16",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "6.16",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)\n\nSashiko notes:\n\n\u003e if SEV initialization fails and KVM is actively running normal VMs, could a\n\u003e userspace process trigger this code path via /dev/sev ioctls (e.g.,\n\u003e SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n\u003e execution for an active VM trigger a general protection fault and crash the\n\u003e host?\n\nRefuse to re-try initialization if SNP is not already initialized for\nSNP_CONFIG.\n\nThis is technically an ABI break: before if SNP initialization failed it\ncould be transparently retriggered by this ioctl, and if no VMs were\nrunning, everything worked fine. Hopefully this is enough of a corner case\nthat nobody will notice, but someone does, there are a few options:\n\n* do something like symbol_get() for kvm and refuse to initialize if KVM is\n loaded\n* check each cpu\u0027s HSAVE_PA for non-zero data before re-initializing\n* once initialization has failed, continue to refuse to initialize until\n the ccp module is unloaded"
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T04:53:06.569Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/345a6e869b33687e9268044bcaeeefd7c61da675"
},
{
"url": "https://git.kernel.org/stable/c/441ea32cf2755a0dc593557056b00b7caa0651f5"
},
{
"url": "https://git.kernel.org/stable/c/20f548cdac94860a164e5ebba4f7e4a01051cb06"
},
{
"url": "https://git.kernel.org/stable/c/08f0e65e784c4b20e6e620dd4f68d8636073a3d2"
}
],
"title": "crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-64307",
"datePublished": "2026-07-25T08:49:40.782Z",
"dateReserved": "2026-07-19T15:36:31.779Z",
"dateUpdated": "2026-08-17T04:53:06.569Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…