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-2026-64309

CVE-2026-64309MEDIUM

Linux Linux — crypto: ccp - Do not initialize SNP for ioctl(SNP_COMMIT)

  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-2026-64309 (Linux). Received CVSS 5.5 and CPE data from NVD.

CWE-908 · CNA: Linux · CVSS v3.1 · 4 references · NVD status: Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Do not initialize SNP for ioctl(SNP_COMMIT) 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? The SNP_COMMIT command does not require the firmware to be in any particular state. Skip initializing it if it was previously uninitialized. The SEV-SNP firmware specification doc 56860 does not mention SNP_COMMIT in Table 5 as a command that is allowed in the UNINIT state, but it is in fact allowed and a future documentation update will reflect that.

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-2026-64309 (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

Weaknesses

CWE-908

References (4)

Authoritative record: CVE-2026-64309 at cve.org

Vendors: linux

Weaknesses: CWE-908

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-64309 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.