CVE-2026-64307 Affecting linux-6.12 package, versions <6.12.100-1~deb12u1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.17% (7th percentile)

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  • Snyk IDSNYK-ECHOLATEST-LINUX612-18579163
  • published7 Aug 2026
  • disclosed25 Jul 2026

Introduced: 25 Jul 2026

CVE-2026-64307  (opens in a new tab)

How to fix?

Upgrade Echo:latest linux-6.12 to version 6.12.100-1~deb12u1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream linux-6.12 package and not the linux-6.12 package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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

CVSS Base Scores

version 3.1