SB20260727262 - Improper Initialization in Linux kernel crypto ccp driver

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Initialization (CVE-ID: CVE-2026-64310)

CWE-ID: CWE-665 - Improper Initialization

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper initialization in the SEV ioctl handling in drivers/crypto/ccp/sev-dev.c when processing /dev/sev ioctl commands that require only SEV firmware. A local user can issue a crafted SEV ioctl request to cause a host crash.

The issue can occur if SEV initialization fails while KVM is actively running normal virtual machines, leading to global clearing of MSR_VM_HSAVE_PA and a general protection fault on the next VMRUN.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/5181e88da99c3d1d41e25db3472a62b8d4b42cdd
• https://git.kernel.org/stable/c/9e983d0a74a6a2348e4ce61647ec8a4dfbe198ac
• https://git.kernel.org/stable/c/d51207735e7c224cf591fa260c557a451a69a5cf
• https://git.kernel.org/stable/c/fb1758e74b8061aacfbce7bbb7a7cc650537e167