What is CVE-2026-64308?

CVE-2026-64308 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 6.12.75 onward and patched in 6.12.96, 6.18.39, 7.1.4 and others. CVE-2026-64308 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-64308?

CVE-2026-64308 has a CVSS score of 5.5 out of 10, rated Medium severity. 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-2026-64308?

Yes, CVE-2026-64308 has been patched. Fixed versions include 6.12.96, 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-2026-64308 actively exploited?

CVE-2026-64308 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-64308

Medium

In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD) 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 SEV firmware docs for SNP_VLEK_LOAD note: > On SNP_SHUTDOWN, the VLEK is deleted. That is, the initialization/shutdown wrapper here is pointless, because the firmware immediately throws away the key anyway. Instead, refuse to do anything if SNP has not been previously initialized. This is an ABI break: before, this was a no-op and almost certainly a mistake by userspace, and now it returns -ENODEV. ABI compatibility could be maintained here by simply returning 0 in the check instead.

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 6.12.96, 6.18.39, 7.1.4, 7.2 and their respective stable series.

Affected from

≥ 6.12.75 ≥ 6.16

Fixed in

✓ 6.12.96 6.12.x ✓ 6.18.39 6.18.x ✓ 7.1.4 7.1.x ✓ 7.2

References

4 total

Kernel Git
https://git.kernel.org/stable/c/61cf5eef20657bff9ca235fe938a99ce5ff65c06

Patch
Kernel Git
https://git.kernel.org/stable/c/8836801847b9479ac046cb18a24981e1b0b05e9d

Patch
Kernel Git
https://git.kernel.org/stable/c/92567ed9306d5a3d1b007eb4faeff30cc3ffc3e4

Patch
Kernel Git
https://git.kernel.org/stable/c/f91e9dbb5845d1e5abf1028e6df57dcf61583e1b

Patch

Details

CVE ID CVE-2026-64308

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-07-25

Modified 2026-09-04

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-64308?

CVE-2026-64308 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 6.12.96, 6.18.39, 7.1.4 and others. CVE-2026-64308 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-64308?

CVE-2026-64308 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-2026-64308?

Yes. CVE-2026-64308 has been patched. Fixed versions include 6.12.96, 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-2026-64308 actively exploited?

No. CVE-2026-64308 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.