CVE-2026-64309

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/5a1364da2f04217a36e2fdfa2db4ee025b383a20	Patch
https://git.kernel.org/stable/c/67ed191b4c8bdf432a3f32d1eb302880b4795cd1	Patch
https://git.kernel.org/stable/c/74768f73854d647a6462f252dc8782ab8a835211	Patch
https://git.kernel.org/stable/c/7a361c74bb12f3398c388905f1d325be642cd36e	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-07-25 10:17

Updated : 2026-09-04 13:05

NVD link : CVE-2026-64309

Mitre link : CVE-2026-64309

CVE.ORG link : CVE-2026-64309

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-908

Use of Uninitialized Resource

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