CVE-2026-64307

Medium

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

Package Linux Kernel
Published 2026-07-25
Last modified 2026-09-04
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected versions

Linux kernel versions 6.12.75, 6.16 and later are affected. Fixed in 6.12.97, 6.18.39, 7.1.4, 7.2 and their respective stable series.

Affected from
≥ 6.12.75 ≥ 6.16
Fixed in
✓ 6.12.97 6.12.x ✓ 6.18.39 6.18.x ✓ 7.1.4 7.1.x ✓ 7.2

References

4 total

Frequently asked questions

  • What is CVE-2026-64307?

    CVE-2026-64307 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.12.75 onward and has been patched in 6.12.97, 6.18.39, 7.1.4 and others. CVE-2026-64307 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-64307?

    CVE-2026-64307 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2026-64307?

    Yes. CVE-2026-64307 has been patched. Fixed versions include 6.12.97, 6.18.39, 7.1.4 and others. If you are running Linux kernel 6.12.75 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-64307 actively exploited?

    No. CVE-2026-64307 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

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