In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Reject attempts to sync VMSA of an already-launched/encrypted vCPU
Reject synchronizing vCPU state to its associated VMSA if the vCPU has
already been launched, i.e. if the VMSA has already been encrypted. On a
host with SNP enabled, accessing guest-private memory generates an RMP #PF
and panics the host.
BUG: unable to handle page fault for address: ff1276cbfdf36000
#PF: supervisor write access in kernel mode
#PF: error_code(0x80000003) - RMP violation
PGD 5a31801067 P4D 5a31802067 PUD 40ccfb5063 PMD 40e5954063 PTE 80000040fdf36163
SEV-SNP: PFN 0x40fdf36, RMP entry: [0x6010fffffffff001 - 0x000000000000001f]
Oops: Oops: 0003 [#1] SMP NOPTI
CPU: 33 UID: 0 PID: 996180 Comm: qemu-system-x86 Tainted: G OE
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Dell Inc. PowerEdge R7625/0H1TJT, BIOS 1.5.8 07/21/2023
RIP: 0010:sev_es_sync_vmsa+0x54/0x4c0 [kvm_amd]
Call Trace:
<TASK>
snp_launch_update_vmsa+0x19d/0x290 [kvm_amd]
snp_launch_finish+0xb6/0x380 [kvm_amd]
sev_mem_enc_ioctl+0x14e/0x720 [kvm_amd]
kvm_arch_vm_ioctl+0x837/0xcf0 [kvm]
kvm_vm_ioctl+0x3fd/0xcc0 [kvm]
__x64_sys_ioctl+0xa3/0x100
x64_sys_call+0xfe0/0x2350
do_syscall_64+0x81/0x10f0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ffff673287d
</TASK>
Note, the KVM flaw has been present since commit ad73109ae7ec ("KVM: SVM:
Provide support to launch and run an SEV-ES guest"), but has only been
actively dangerous for the host since SNP support was added. With SEV-ES,
KVM would "just" clobber guest state, which is totally fine from a host
kernel perspective since userspace can clobber guest state any time before
sev_launch_update_vmsa().
References
Configurations
Configuration 1 (hide)
|
History
29 Apr 2026, 14:29
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | NVD-CWE-noinfo | |
| First Time |
Linux
Linux linux Kernel |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| References | () https://git.kernel.org/stable/c/692fdf05e55fa03960a1278afdc2478c12daea13 - Patch | |
| References | () https://git.kernel.org/stable/c/6ef109e01e1d35199e1a97ea68bdfd3cf3fbf9ab - Patch | |
| References | () https://git.kernel.org/stable/c/8f85a4885eee8cb495961ffa371a91828afb9445 - Patch | |
| References | () https://git.kernel.org/stable/c/9b9f7962e3e879d12da2bf47e02a24ec51690e3d - Patch | |
| References | () https://git.kernel.org/stable/c/c9609847ae65ca36233077c2b6cb2bc0fb37c77a - Patch |
27 Apr 2026, 12:16
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
24 Apr 2026, 15:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-24 15:16
Updated : 2026-04-29 14:29
NVD link : CVE-2026-31593
Mitre link : CVE-2026-31593
CVE.ORG link : CVE-2026-31593
JSON object : View
Products Affected
linux
- linux_kernel
CWE
