Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-64310
Linux Linux — crypto: ccp - Do not initialize SNP for SEV ioctls
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0017 5.6 —
AFFECTED
Product Versions Fixed
Linux 1c3506ea8599a3ad1b9aae5cbd573134f8d18db7 – —
Linux 6.16 – 6.12.96
TIMELINE
Jul 19 Reserved by Linux
Jul 25 Published (CNA: Linux)
Sep 4 ENRICHED — CVE-2026-64310 (Linux). Received CVSS 5.5 and CPE data from NVD.
Description
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Do not initialize SNP for SEV ioctls
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?
sev_move_to_init_state() is called for ioctls requiring only SEV firmware:
SEV_PEK_GEN, SEV_PDH_GEN, SEV_PEK_CSR, SEV_PEK_CERT_IMPORT, and
SEV_PDH_CERT_EXPORT. After the firmware command, it does SEV_SHUTDOWN on
the SEV firmware. Since these commands do not require SNP to be
initialized, skip it by calling __sev_platform_init_locked() which only
initializes the SEV firmware. This way SNP is not Initialized at all, and
HSAVE_PA is not cleared.
The previous code saved any SEV initialization firmware error to
init_args.error and then threw it away and hardcoded the return value of
INVALID_PLATFORM_STATE regardless of the real firmware error. This patch
changes it to surface the underlying error, which is hopefully both more
useful and doesn't cause any problems.
Note that it is still safe to call __sev_firmware_shutdown() directly: it
calls __sev_snp_shutdown_locked(), which skips SNP shutdown if SNP was not
initialized.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| July 19, 2026 | Reserved | Reserved by Linux |
| July 25, 2026 | Published | Published (CNA: Linux) |
| September 4, 2026 | ENRICHED | ENRICHED — CVE-2026-64310 (Linux). Received CVSS 5.5 and CPE data from NVD. |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 1c3506ea8599a3ad1b9aae5cbd573134f8d18db7 | — |
| Linux | Linux | — | 6.16 | 6.12.96 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-64310 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.