{"api_version":"1","generated_at":"2026-08-04T07:35:37+00:00","cve":"CVE-2026-64307","urls":{"html":"https://cve.report/CVE-2026-64307","api":"https://cve.report/api/cve/CVE-2026-64307.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64307","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64307"},"summary":{"title":"crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)","description":"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> if SEV initialization fails and KVM is actively running normal VMs, could a\n> userspace process trigger this code path via /dev/sev ioctls (e.g.,\n> SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n> execution for an active VM trigger a general protection fault and crash the\n> 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's 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","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-25 10:17:11","updated_at":"2026-07-25 10:17:11"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/345a6e869b33687e9268044bcaeeefd7c61da675","name":"https://git.kernel.org/stable/c/345a6e869b33687e9268044bcaeeefd7c61da675","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/20f548cdac94860a164e5ebba4f7e4a01051cb06","name":"https://git.kernel.org/stable/c/20f548cdac94860a164e5ebba4f7e4a01051cb06","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/441ea32cf2755a0dc593557056b00b7caa0651f5","name":"https://git.kernel.org/stable/c/441ea32cf2755a0dc593557056b00b7caa0651f5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/08f0e65e784c4b20e6e620dd4f68d8636073a3d2","name":"https://git.kernel.org/stable/c/08f0e65e784c4b20e6e620dd4f68d8636073a3d2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64307","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64307","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1c3506ea8599a3ad1b9aae5cbd573134f8d18db7 345a6e869b33687e9268044bcaeeefd7c61da675 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ceac7fb89e8da465aec3ac3c20477f912f5c3a6c 441ea32cf2755a0dc593557056b00b7caa0651f5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ceac7fb89e8da465aec3ac3c20477f912f5c3a6c 20f548cdac94860a164e5ebba4f7e4a01051cb06 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ceac7fb89e8da465aec3ac3c20477f912f5c3a6c 08f0e65e784c4b20e6e620dd4f68d8636073a3d2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.75 6.12.97 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.16","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.16 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.97 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.39 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.4 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64307","cve":"CVE-2026-64307","epss":"0.002150000","percentile":"0.121210000","score_date":"2026-07-28","updated_at":"2026-07-29 00:05:33"},"legacy_qids":[]},"source_records":{"cve_program":{"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-rc1","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-rc1","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> if SEV initialization fails and KVM is actively running normal VMs, could a\n> userspace process trigger this code path via /dev/sev ioctls (e.g.,\n> SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n> execution for an active VM trigger a general protection fault and crash the\n> 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's 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":"2026-07-25T08:49:40.782Z","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":"2026-07-25T08:49:40.782Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-25 10:17:11","lastModifiedDate":"2026-07-25 10:17:11","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64307","Ordinal":"1","Title":"crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)","CVE":"CVE-2026-64307","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64307","Ordinal":"1","NoteData":"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> if SEV initialization fails and KVM is actively running normal VMs, could a\n> userspace process trigger this code path via /dev/sev ioctls (e.g.,\n> SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n> execution for an active VM trigger a general protection fault and crash the\n> 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's 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","Type":"Description","Title":"crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)"}]}}}